Glossary

A
Absolute Advantage
  1. An economics concept in which one party has a direct advantage in efficiency in producing/providing a specific good or service over another party.
Address
  1. A blockchain public address is a unique alphanumeric string that is used to identify users in the blockchain. The public address can also be used to reference, send, or receive transactions (see definition), or where you’d like to receive, send, or record blockchain transactions. An example of a blockchain address is: 5TdA55HeLopzzwe3Lg7W335tGdCc623PoQ
    Reference: MIT
  2. A 20-byte hash formatted using base58check to produce either a P2PKH or P2SH Bitcoin address. Currently, the most common way users exchange payment information. Not To Be Confused with IP address.
  3. Blockchain addresses operate in a similar way to physical addresses and are used to send or receive transactions on a blockchain network. An address usually presents itself as a string of alphanumeric characters.
  4. A secure identifier marked by a unique string of characters that enables payments to an individual or entity via blockchain transactions. It usually requires a private key to exclusively access the funds. For example, Bitcoin addresses are alphanumeric strings that begin with a 1 or 3; Ethereum addresses begin with '0x'.
  5. Used to send and receive cryptocurrency. Usually, the address is a line of letters and numbers. Also, it is a public key used by bitcoin-owners for the transaction digital signature.
  6. Cryptocurrency addresses are used to send or receive transactions on the network. An address usually presents itself as a string of alphanumeric characters.
  7. A string of letters and numbers that are used to receive cryptocurrency. Works similar to a traditional bank account number and can be shared publicly with others.
  8. These are usually used to receive and send transactions on the network. Associate degree address may be a string of alphanumerical characters, however, may be delineated as a scannable QR code.
  9. A string of letters and numbers that people use to send bitcoin to or from. A bitcoin address is shared from one user to another user so that they can send you Bitcoin. Likewise, if you want to send bitcoin to someone you will need their address (obtained from their wallet).
  10. A Bitcoin address is similar to a physical address or an email. It is the only information you need to provide for someone to pay you with Bitcoin. An important difference, however, is that each address should only be used for a single transaction.
  11. Used to receive and send transactions on the blockchain network. It contains a string of alphanumeric characters, but can also be represented as a scannable QR code.
  12. Used to send and receive transactions. An address is often a hashed version of a public key.
Addy
  1. This trading slang term refers to a cryptocurrency public address (or key). For example: “Tell me your addy, please.”
Agreement Ledgers
  1. distributed ledgers used by two or more parties to negotiate and reach an agreement.
Airdrop
  1. A method of distributing cryptocurrency amongst a population first attempted with Auroracoin in early 2014.
  2. An airdrop is a marketing strategy whereby coins are arbitrarily deposited into wallets for free in an effort to get crypto enthusiasts curious about the coin.
  3. A free distribution of coins or tokens to potential users.
Algorithm
  1. A set of mathematical instructions or rules that need to be followed in problem solving. For reference, there exists various algorithms to solve a rubix cube. If the algorithm is applied correctly, the outcome is that the cube will be solved.
  2. A sequence of unambiguous instructions used for the purpose of solving a problem.
All or None Order (AON)
  1. An order that must be executed in its entirety or not executed at all.
All Time High (ATH)
  1. This means that the price of a certain cryptocurrency has broken all its past records and is trading at the highest price it has ever achieved.
  2. Refers to the maximum price of an asset, higher than at any other time in its trading history. Cryptocurrencies have risen dramatically, creating many consecutive ATHs.
  3. ATH is an acronym for “All-Time-High”. This is the highest historical price of any currency in the entirety of its life.
  4. The highest price of a cryptocurrency in a quote​ currency, such as a dollar, BTC, ETH, or BNB
Allocation
  1. Percentage distribution of tokens. For example, a project may allocate 40% of tokens to their team.
Alpha
  1. A first look at a product released by a team to get feedback, usually in a less mature state than in beta.
Altcoins // Alt Coins // Alt-coins
  1. This is associate degree abbreviation of “Bitcoin alternative”. Currently, the bulk of altcoins area unit forks of Bitcoin with sometimes minor changes to the proof of labour (POW) algorithmic rule of the Bitcoin blockchain. The foremost distinguished altcoin is Litecoin.
  2. Describes all cryptocurrencies that are not Bitcoin - like Ethereum, Litecoin, and Monero. It is short for "Alternative Coin" (AKA coins that were created after Bitcoin).
  3. Is an abbreviation of “Bitcoin alternative”. Currently, the majority of altcoins are forks of Bitcoin with usually minor changes to the proof of work (POW) algorithm of the Bitcoin blockchain. The most prominent altcoin is Litecoin. Litecoin introduces changes to the original Bitcoin protocol such as decreased block generation time, increased maximum number of coins and different hashing algorithm
  4. Generally any cryptocurrency other than Bitcoin or Ethereum — though some Bitcoin folks would probably still say Ethereum is an altcoin. Altcoin is an abbreviation of “Bitcoin alternative.” Altcoins are their own cryptocurrency and run on their own native blockchain (see tokens for a differentiation from altcoins or ‘coins’). Currently, the majority of altcoins are forks of Bitcoin with usually minor changes to the proof of work (POW) algorithm of the Bitcoin blockchain. The most prominent altcoin is Litecoin. Litecoin introduces changes to the original Bitcoin protocol such as decreased block generation time, increased maximum number of coins and different hashing algorithm
  5. A cryptocurrency or a category of cryptocurrencies that are an alternative to bitcoin. Many altcoins project themselves as better alternatives to bitcoin in various ways (e.g. more efficient, less expensive, etc.).
  6. Altcoin is an abbreviation of “Bitcoin alternative”. Currently, the majority of altcoins are forks of Bitcoin with usually minor changes to the proof of work (POW) algorithm of the Bitcoin blockchain. The most prominent altcoin is Litecoin. Litecoin introduces changes to the original Bitcoin protocol such as decreased block generation time, increased maximum number of coins and different hashing algorithm
  7. A cryptocurrency that works similarly to bitcoin, but with modifications, for example, being able to process transactions faster.
    Reference: MIT
  8. Any cryptocurrency that exists as an alternative to bitcoin
  9. A cryptocurrency that is alternative to Bitcoin. Used to describe cryptocurrencies that are not Bitcoin.
Anti Money Laundering (AML)
  1. Laws and regulations in the United States and other countries to prevent illegal activities. Compells exchanges and other money transmitters to report suspicious activity.
  2. A framework consisting of legal and regulatory procedures to minimize and curb the flow of funds that are generated from illegal or dubious activities.
Application Programming Interface (API)
  1. Application programming interface (part of a remote server that sends requests and receives responses)
  2. A collection of functions and procedures that allow users to interact/communicate with the data of an application or service, such as an exchange, to execute the features of the service programmatically.
Arbitrage
  1. Taking advantage of the price difference of an asset in two different markets or exchanges, often internationally. The price difference is used for a quick profit.
  2. Arbitrage is a trading practice where a trader takes advantage of the difference in price of the same commodity on two different exchanges. Basically, a trader would buy an asset on one exchange and then sell it at a higher price on another exchange, thus taking advantage of the difference in price between the two exchanges.
  3. Buying and selling of assets over different markets in order to take advantage of differing prices on the same asset.
ASIC
  1. Short for Application Specific Integrated Circuit. Often compared to GPUs, ASICs are specially made for mining and may offer significant power savings. An ASIC is a computer processing chip that is designed to perform one function only, whereas most modern computers have multi-thread CPUs that allow the computer to complete a range of tasks all at the same time. In the crypto space, an ASIC computer is used to mine bitcoin.
  2. An “Application Specific Integrated Circuit” is a silicon chip specifically designed to do a single task. In the case of Bitcoin, they are designed to process SHA-256 hashing problems to mine new bitcoins. ASICs are considered to be much more efficient than conventional hardware(CPUs, GPUs). Using a regular computer for Bitcoin mining is seen as unprofitable and only results in higher electricity bill
  3. Is an acronym for “Application Specific Integrated Circuit”. ASICs are silicon chips specifically designed to do a single task. In the case of bitcoin, they are designed to process SHA-256 hashing problems to mine new bitcoins.
  4. A type of computer chip. For cryptocurrencies, it's used to mine new coins efficiently (see mining below). Short for Application Specific Integrated Circuit.
  5. ASIC is the short form for “Application-Specific Integrated Circuit”, a silicon chip specifically designed to do a single task. Basically, the computers we use to operate on general-purpose circuits, while an ASIC is utilized entirely for a single application. In the case of cryptocurrency mining, ASICs can be used to greatly increase efficiency and significantly decrease energy costs.
  6. Is a special circuit optimized for the cryptocurrency mining, and it comes with this function more effectively than computer GPU and CPU.
  7. Short form for ‘Application Specific Integrated Circuit’. Often compared to GPUs, ASICs are specially made for mining and may offer significant power savings.
  8. Short form for ‘Application Specific Integrated Circuit’. Often compared to GPUs, ASICs are specially made for mining and may offer significant power savings.
  9. An “Application Specific Integrated Circuit” is a silicon chip specifically designed to do a single task. In the case of Bitcoin, they are designed to process SHA-256 hashing problems to mine new bitcoins. ASICs are considered to be much more efficient than conventional hardware(CPUs, GPUs). Using a regular computer for Bitcoin mining is seen as unprofitable and only results in higher electricity bill
  10. An Integrated Circuit customized for maximum performance in a particular use, rather than general-purpose use.
ASIC-resistant
  1. Achieved by requiring a large amount of memory when mining. This means that additional physical area is needed on the chip. As a result an ASIC would experience no significant speed increase.
Asymmetric Cryptography
  1. Asymmetric cryptography is also known as public key cryptography. It uses public and private keys to encrypt and decrypt data. The keys are large numbers that have been paired together but are not identical (asymmetric). A public key can be shared with everyone. The private key in the pair is kept secret. Protocols such as SSH, S/MIME rely on asymmetric cryptography for encryption and digital signature functions.
Atomic Swap // Atomic Swaps
  1. An atomic swap, or sometimes called atomic cross-chain trading, is the exchange of one cryptocurrency to another cryptocurrency without the need to trust a third party. It’s called atomic (referring to the Greek term atomon, i.e. indivisible) since there aren’t two separate transfers, but one single transfer that does the swap at once.
  2. Atomic swaps involve cryptocurrencies that are tradeable with one another without needing an exchange in the middle. Typically, they have to follow the same encryption standard and have a payment channel protocol such as Lightning Network. With what’s called a hash-time locked smart contract, two individuals can trustlessly trade cryptocurrency pairs with one another: solving the interoperability piece.
Attack surface
  1. Different points in software environments where an attacker can attempt to enter data or extract data.
Attestation Ledger
  1. Distributed ledgers that provide a durable record of agreements, commitments or statements, providing evidence (attestation) that these agreements, commitments or statements were made.
  2. A distributed ledger that codifies agreements, statements, and other facts into the Blockchain. Can provide evidence to "attest" that something actually happened.
  3. An Attestation Ledger is a distributed ledger that provides a reviewable record of agreements, commitments, statements, or transactions. The purpose is to provide evidence, or attestation, of the nature and fulfillment of an agreement. These viewable records are, in essence, receipts. This type of ledger is vital to compliance with government and tax regulations.
  4. These area units distributed ledgers that give a sturdy record of agreements, commitments or statements, providing proof (attestation) that these agreements, commitments or statements were created.
Autonomous Agent
  1. these are software apps and modules that can make decisions without any participation and approval on the human part.
B
Bagholder
  1. A person who is still holding an asset after a pump and dump scheme (see below). Can also refer to somebody who is believing in and holding a coin that's declining in value.
Base58check
  1. The method used in Bitcoin for converting 160-bit hashes into P2PKH and P2SH addresses. Also used in other parts of Bitcoin, such as encoding private keys for backup in WIP format. Not the same as other base58 implementations. Not To Be Confused With: P2PKH address || P2SH address || IP address
Bear
  1. A person who is pessimistic about market prices and expects them to go down. This person is also known to be "bearish" about the market and price expectations.
Bear Market
  1. When the market is a Bear Market, it means that the general sentiment and expectation of the market is that price is going to decrease, either for a single coin or asset or in the market as a whole. This expectation is generally a self-fulfilling prophecy, resulting in price drops for individual assets or for all assets across the market as a whole. This trend continues to increase until sentiment changes, and a more Bull Market mentality starts to move prices back up.
Bear Trap
  1. A false market signal where the rising trend of an asset appears to be turning down, but actually is not. Short sellers are forced to exit their positions to stop losing money.
BearWhale
  1. This trading slang term means a trader with a fat account who is bearish on the price of a cryptocurrency.
Best Block Chain
  1. A chain of blocks with each block referencing the block that preceded it. The most-difficult-to-recreate chain is the best blockchain. Not To Be Confused With: Header chain
Best Header Chain
  1. A chain of block headers with each header linking to the header that preceded it; the most-difficult-to-recreate chain is the best header chain. Not To Be Confused With: Block chain
Bitcoin
  1. with a capital “B” refers to the protocol – the code, the nodes, the network and their peer-to-peer interaction.
  2. The decentralized, peer-to-peer network that maintains the blockchain. The Bitcoin network processes all Bitcoin transactions.
  3. Is a cryptocurrency that runs on a (1) global peer to peer network, is (2) decentralised (no single entity can control it), it’s (3) open source (wallet & transaction verification), (4) bypassing middlemen or central authority, with (5) no issuer or acquirer, (6) anyone with a computer or smartphone can use it
  4. Bitcoin - with capitalization, is used when describing the concept of Bitcoin, or the entire network itself. e.g. "I was learning about the Bitcoin protocol today." bitcoin - without capitalization, is used to describe bitcoins as a unit of account. e.g. "I sent ten bitcoins today."; it is also often abbreviated BTC or XBT.
bitcoin (BTC)
  1. Bitcoin is the first decentralized, open-source cryptocurrency that runs on a global peer-to-peer network, without the need for middlemen and a centralized issuer.
    Reference: MIT
  2. With a lowercase ‘b’ refers to the currency – the cryptocurrency we send and receive, via the Bitcoin network.
  3. Bitcoin is the first widely-recognized cryptocurrency and has been the pioneer of the Blockchain industry as a whole.
  4. The first, and most popular, cryptocurrency based on the decentralized ledger of a blockchain
  5. Bitcoin is the first decentralized, open source cryptocurrency that runs on a global peer to peer network, without the need for middlemen and a centralized issuer.
  6. Bitcoin is a digital currency (also called crypto-currency) that is not backed by any country's central bank or government. Bitcoins can be traded for goods or services with vendors who accept Bitcoins as payment. Bitcoin-to-Bitcoin transactions are made by digitally exchanging anonymous, heavily encrypted hash codes across a peer-to-peer (P2P) network. The P2P network monitors and verifies the transfer of Bitcoins between users. Each user's Bitcoins are stored in a program called a digital wallet, which also holds each address the user sends and receives Bitcoins from, as well as a private key known only to the user. The Bitcoin network is designed to mathematically generate no more than 21 million Bitcoins and the network is set up to regulate itself to deal with inflation. Bitcoins can be spent by initiating a transfer request from a Bitcoin address in the customer's wallet to a Bitcoin address in the vendor's wallet.
Bitcoin ATM
  1. A cash point where people can trade fiat currency and bitcoins
Bitcoin Cash (BCH)
  1. Bitcoin Cash is a cryptocurrency that was created as a Bitcoin hard fork in August 2017. Bitcoin Cash is essentially a clone of the Bitcoin blockchain but has improved scalability by increasing block size capacity from 1 MB to 8 MB. The goal is to make Bitcoin Cash a more usable currency in comparison with Bitcoin.
  2. A clone (AKA "fork") of Bitcoin that focuses on processing high volumes of transactions differently. Created because of disagreements about how to best grow digital currency.
  3. A type of cryptocurrency that was created in August 2017 and is essentially a clone of the Bitcoin blockchain but has increased block size capacity (from 1 MB to 8 MB) as a way to solve the scaling problem.
Bitcoin Dominance
  1. The ratio of Bitcoin's market capitalization versus the sum of the market capitalizations of all cryptocurrencies.
Bitcoin Protocol
  1. The open source, cryptographic protocol which operates on the Bitcoin network, setting the “rules” for how the network runs.
BitLicense
  1. The controversial business license issued for cryptocurrency companies in New York. Created and provided by the New York State Department of Financial Services (NYSDFS).
Black Swan Event
  1. An event that is often entirely unexpected and deviates from the expected result causing widespread ramifications.
Block 0
  1. The first block in the Bitcoin blockchain. Synonyms: Genesis block Not To Be Confused With: Generation transaction (the first transaction in a block)
Block Ciphers
  1. A Block Cipher is a method of encryption that encrypts data/text in chunks, called blocks, rather than each bit individually. In blockchain, Block Ciphers are the primary method of encrypting and recording the chained blocks. Each block contains a cipher and an algorithm to apply the cipher to the block. Once encrypted, the block is now in ciphertext form, and requires the encryption key to be read.
  2. are a method of encrypting text (to produce ciphertext) in which a cryptographic key and algorithm are applied to a block of data at once as a group rather than to one bit at a time.
Block Explorer
  1. An online tool for exploring the blockchain of a particular cryptocurrency, where you can watch and follow live all the transactions happening on the blockchain. Block explorers can serve as blockchain analysis and provide information such as total network hash rate, coin supply, transaction growth, etc.
  2. A Block Explorer is a tool used to look inside the data stored on a blockchain. It has a record of all the transactions in each block, and is often made public to increase blockchain visibility and transparency. In essence, a Block Explorer is much like a web browser for the internet. It’s a friendly UI that displays the information at given block locations. There are several prominent blockchain explorers that are free to use, such as Blockchain.info for the Bitcoin blockchain and Etherscan.io for the Ethereum blockchain.
  3. Block explorer is an online tool to view all transactions, past and current, on the blockchain. They provide useful information such as network hash rate and transaction growth.
  4. A tool to see detailed information on transactions, accounts, and other activity on a Blockchain. Depending on the cryptocurrency, sweeping data or limited data is available.
  5. An online Blockchain webpage which allows users to browse information about blocks, transactions, balances, and transaction histories.
Block Halving
  1. Bitcoin's supply of new coins issued to miners is cut in half about every four years to keep it scarce. This 50% cut is known as the halving. The next halving will be around 2020.
  2. A reduction in the block reward given to crypto-currency miners once a certain number of blocks have been mined. The Bitcoin block mining reward halves every 210,000 blocks
  3. Bitcoins have a finite supply, which makes them a scarce digital commodity. The total amount of bitcoins that will ever be issued is 21 million. The number of bitcoins generated per block is decreased by 50% every four years. This is called “halving.” The final halving will take place in the year 2140.
  4. Bitcoins have a finite supply, which makes them a scarce digital commodity. The total amount of bitcoins that will ever be issued is 21 million. The number of bitcoins generated per block is decreased by 50% every four years. This is called “halving.” The Bitcoin block mining reward halves every 210,000 blocks. The final halving will take place in the year 2140.
Block Header
  1. An 80-byte header belonging to a single block which is hashed repeatedly to create proof of work. Synonyms: Block header || Header
Block Height
  1. Block Height is a measure of how large a blockchain is based on the number of blocks appended to the chain. For instance, if a blockchain has 100 blocks, its block height would be 100. The first block in any chain, called the Genesis Block, is given the height of 0, and each block after just follows the numerical order.
  2. Refers to the total number of blocks on a given cryptocurrency blockchain. It starts with the first block, also known as the Genesis Block (Height 0) and counts up from there.
  3. The number of blocks connected on the blockchain.
  4. Refers to the number of blocks connected together in the blockchain. For example, Height 0, would be the very first block, which is also called the Genesis Block.
  5. The number of blocks preceding a particular block on a blockchain. For example, the genesis block has a height of zero because zero block preceded it.
  6. The number of blocks in the chain between itself and the first block on that blockchain (genesis block or block 0).
Block Reward
  1. An amount of Bitcoin that miners earn upon creating a block (of pending transactions). The reward is equal to the sum of 1) the block subsidy (newly ‘minted’ satoshis) plus all transactions fees attached to transactions included in that block. The subsidy reward is halved every four years.
  2. Are rewards given to a miner which has successfully hashed a transaction block. Block rewards can be a mixture of coins and transaction fees, depending on the policy used by the cryptocurrency in question, and whether all of the coins have already been successfully mined. The current block reward for the Bitcoin network is 25 bitcoins for each block.
  3. The amount that miners may claim as a reward for creating a block. Equal to the sum of the block subsidy (newly available satoshis) plus the transactions fees paid by transactions included in the block.
  4. The amount that miners may claim as a reward for creating a block. Equal to the sum of the block subsidy (newly available satoshis) plus the transactions fees paid by transactions included in the block. Not To Be Confused With: Block subsidy or Transaction fees
  5. A form of incentive for the miner who successfully calculated the hash in a block during mining. Verification of transactions on the blockchain generates new coins in the process, and the miner is rewarded a portion of those.
  6. An amount of crypto-currency a miner receives for processing transactions in a given block. Because creating (or “mining”) blocks is so crucial to the security of the Bitcoin network and yet so hard, the Bitcoin protocol includes a mechanism to encourage people to mine: every time a block is added, the miner who found the block is given 12,5 BTC(this number will change at the next halving in 2020) as a block reward
  7. If people are going to be pointing some of their computing power to the Bitcoin network, then they need to get paid for their work. This is where block rewards come into play. New bitcoins are created every ten minutes, and those bitcoins are rewarded to the Bitcoin miner who is able to find the answer to the abovementioned mathematical equations before anyone else. In addition to the block reward, which is cut in half roughly every four years, miners are also rewarded with the transaction fees from all transfers of value that took place since the last block was mined. Without these valuable rewards for mining, there would be no reason for miners to point computing power to the Bitcoin network, and the network could not be secure without the large amount of computing power needed to attack the network.
Block Size
  1. Shows the file size of each block on a blockchain and therefore how many transactions can be bundled and processed in each one. For Bitcoin, the current block size is 1MB.
  2. The maximum size in bytes that the consensus rules allow a block to be. The current block size limit is 1000000 bytes.
Block(s)
  1. Refers to a collection of data related to transactions that are bundled together with a predetermined size and are processed for transaction verification and eventually becomes part of a blockchain.
  2. Is a functional unit in the blockchain that contains transaction records. New blocks are added to the blockchain as a result of mining. The capacity of each block is 1 MB.
  3. A collection of transactions that have happened during a certain amount of time (10 minutes for Bitcoin). The transactions are bundled in a block and added to the Blockchain.
  4. Transactions from the network fill blocks. And, as the transactions are validated, they are compiled into the blockchain permanently. Blocks include a timestamp. They’re built in such a way that they cannot be changed once recorded.
  5. Blocks are data packages that include a few necessary parts. These parts include a reference to the block immediately preceding the current block, the solution to a very complicated mathematical problem or puzzle (without which the block cannot be recorded in the chain. The process of solving the puzzle and recording the block is called “mining”), and a record of the machine that gets the reward for solving the puzzle. The most important part is the general ledger of the transactions that were completed since the last block was recorded. Blocks are chained together in chronological order, thus the source of the name “blockchain”.
  6. A block is the data structure used in blockchains to group transactions. in addition to transactions, blocks include other elements such as the hash of the previous block and a timestamp.
  7. A block is a record in the block chain that contains and confirms many waiting transactions. Roughly every 10 minutes, on average, a new block including transactions is appended to the block chain through mining.
  8. A package of data containing multiple transactions over a given period of time.
  9. Packages of data that carry permanently recorded information on the Blockchain network. The data is related to transactions that are bundled together with a predetermized size, which are processed for transaction verification, eventually becoming part of the blockchain.
  10. A block is a collection of transactions. Blocks are synonymous with digital pages in a ledger, also known as a record-keeping book. These files store unalterable data related to the network.
    Reference: MIT
  11. A group of Bitcoin transactions that have taken place during a specific time period. The average is around 10 minutes. Miners process Bitcoin transactions not one-by-one but in groups or “blocks”.
  12. Block (on the Bitcoin Blockchain) Data is permanently recorded on the Bitcoin network through files called blocks. A block is a record of some or all of the most recent Bitcoin transactions that have not yet been recorded in any prior blocks. New blocks are added to the end of the record (known as the blockchain), and can never be changed or removed once written (although some software will remove them if they are orphaned). Each block memorializes what took place in the minutes before it was created. Each block contains a record of some or all recent transactions and a reference to the block that came immediately before it. It also contains an answer to a difficult-to-solve mathematical puzzle – the answer to which is unique to each block. New blocks cannot be submitted to the network without the correct answer – the process of “mining” is essentially the process of competing to be the next to find the answer that “solves” the current block. The mathematical problem in each block is extremely difficult to solve, but once a valid solution is found, it is very easy for the rest of the network to confirm that the solution is correct. There are multiple valid solutions for any given block – only one of the solutions needs to be found for the block to be solved. Because there is a reward of brand new bitcoins for solving each block, every block also contains a record of which Bitcoin addresses or scripts are entitled to receive the reward. This record is known as a generation transaction, or a coinbase transaction, and is always the first transaction appearing in every block. The number of Bitcoins generated per block starts at 50 and is halved every 210,000 blocks (about four years). Bitcoin transactions are broadcast to the network by the sender, and all peers trying to solve blocks collect the transaction records and add them to the block they are working to solve. Miners get an incentive to include transactions in their blocks because of attached transaction fees. The difficulty of the mathematical problem is automatically adjusted by the network, such that it targets a goal of solving an average of 6 blocks per hour. Every 2016 blocks (solved in about two weeks), all Bitcoin clients compare the actual number created with this goal and modify the target by the percentage that it varied. The network comes to a consensus and automatically increases (or decreases) the difficulty of generating blocks. Because each block contains a reference to the prior block, the collection of all blocks in existence can be said to form a chain. However, it’s possible for the chain to have temporary splits – for example, if two miners arrive at two different valid solutions for the same block at the same time, unbeknownst to one another. The peer-to-peer network is designed to resolve these splits within a short period of time so that only one branch of the chain survives. The client accepts the ‘longest’ chain of blocks as valid. The ‘length’ of the entire blockchain refers to the chain with the most combined difficulty, not the one with the most blocks. This prevents someone from forking the chain and creating a large number of low-difficulty blocks and having it accepted by the network as ‘longest’
  13. One or more transactions prefaced by a block header and protected by proof of work. Blocks are the data stored on the blockchain.
  14. Blocks are packages of data that carry permanently recorded data on the blockchain network.
  15. Block is defined as a single digital record created within a blockchain. Each block contains a record of the previous block, and when linked together these become the “chain”. Blockchain tech creates permanent, secure digital recordings. It can record any information, but it started with recording bitcoin transactions. If you imagine the blockchain as a book of records, then each page in that book is what is known as a “block”. Blocks are attached to each other making what is known as the blockchain.
Blockchain // Block chain
  1. The blockchain is one type of a distributed ledger. Distributed ledgers use independent computers (referred to as nodes) to record, share and synchronize transactions in their respective electronic ledgers (instead of keeping data centralized as in a traditional ledger). Blockchain organizes data into blocks, which are chained together in an append-only mode. Blockchain/ DLT are the building block of “internet of value,” and enable recording of interactions and transfer “value” peer-to-peer, without a need for a centrally coordinating entity. “Value” refers to any record of ownership of asset -- for example, money, securities, land titles -- and also ownership of specific information like identity, health information and other personal data.
  2. The block chain is a public record of Bitcoin transactions in chronological order. The block chain is shared between all Bitcoin users. It is used to verify the permanence of Bitcoin transactions and to prevent double spending.
  3. The idea emerges that the Bitcoin blockchain may of course use for any quite worth dealings or any quite agreement reminiscent of P2P insurance, P2P energy mercantilism, P2P ride sharing, etc. Coloured Coins and Mastercoin tries to resolve that downside supports the Bitcoin Blockchain Protocol. Private organizations like banks understood that they may use the plan of blockchain as a distributed ledger technology (DLT), and make blockchain (private or federated) that permissions, wherever the validator can a member of a syndicate or separate legal entities of an equivalent organization. The term blockchain within the context of permissioned non-public ledger is extremely polemical and controversial. This can why the term distributed ledger technologies emerge as a lot of general terms. There are 3 Popular types of Blockchains you need to know namely: - Permissionless Blockchain - Public Permissioned Blockchain - Private Permissioned Blockchain
  4. A blockchain is a shared ledger where transactions are permanently recorded by appending blocks. The blockchain serves as a historical record of all transactions that ever occurred, from the genesis block to the latest block, hence the name blockchain.
    Reference: MIT
  5. Blockchain is a distributed ledger, or database, shared across a public or private computing network. Each computer node in the network holds a copy of the ledger, so there is no single point of failure. Every piece of information is mathematically encrypted and added as a new “block” to the chain of historical records. Various consensus protocols are used to validate a new block with other participants before it can be added to the chain. This prevents fraud or double spending without requiring a central authority. The ledger can also be programmed with “smart contracts,” a set of conditions recorded on the blockchain, so that transactions automatically trigger when the conditions are met. For example, smart contracts could be used to automate insurance-claim payouts. Blockchain’s core advantages are decentralization, cryptographic security, transparency, and immutability. It allows information to be verified and value to be exchanged without having to rely on a third-party authority. Rather than there being a singular form of blockchain, the technology can be configured in multiple ways to meet the objectives and commercial requirements of a particular use case.
  6. A structure for storing data in which groups of valid transactions, called blocks, form a chronological chain, with each block cryptographically linked to the previous one.
  7. A decentralized, digital ledger where transactions made in Bitcoin or other cryptocurrencies are recorded chronologically and publicly. The block contains information that, once it goes into the blockchain, it becomes part of the permanent and immutable database, connecting to other blocks in the blockchain like the links in a chain.
  8. A type of distributed digital ledger to which data is recorded sequentially and permanently in ’blocks’. Each new block is linked to the immediately previous block with a cryptographic signature, forming a ‘chain’. This tamper-proof self-validation of the data allows transactions to be processed and recorded to the chain without recourse to a third party certification agent. The ledger is not hosted in one location or managed by a single owner, but is shared and accessed by anyone with the appropriate permissions – hence ‘distributed’.
  9. Blockchains are distributed ledgers, secured by cryptography. They are essentially public databases that everyone can access and read, but the data can only be updated by the data owners. Instead of the data residing on a single centralized server, the data is copied across thousands and thousands of computers worldwide. The consecutive string of every block ever executed makes up a blockchain. A distributed database of chronologically ordered transactions; these are all of the validated transactions that have ever been executed.
  10. Shared, trusted, public ledger of transactions, that everyone can inspect but which no single user controls. It is a cryptographed, secure, tamper-resistant distributed database. It solves a complex mathematical problem to exist. A blockchain is a perfect place to store value, identities, agreements, property rights, credentials, etc. Once you put something like a Bitcoin into it, it will stay there forever. It is decentralized, disintermediated, cheap and censorship-resistant. Applications of Blockchain: Bitcoin (cryptocurrency), Namecoin (wants to replace the entire DNS system of the Internet), or Sia (a decentralized cloud storage), Ethereum (Turing complete Virtual Machine where you can run any smart contract); Any centralized service like eBay, Dropbox can potentially be built in a decentralized way using blockchain technology, considerably lowering transaction costs
    Reference:
  11. A blockchain is a shared ledger where transactions are permanently recorded by appending blocks. The blockchain serves as a historical record of all transactions that ever occurred, from the genesis block to the latest block, hence the name blockchain.
  12. Blockchain (Public) A mathematical structure for storing digital transactions (or data) in an immutable, peer-to-peer ledger that is incredibly difficult to fake and yet remains accessible to anyone.
  13. Blocks are data packages that include a few necessary parts. These parts include a reference to the block immediately preceding the current block, the solution to a very complicated mathematical problem or puzzle (without which the block cannot be recorded in the chain. The process of solving the puzzle and recording the block is called “mining”), and a record of the machine that gets the reward for solving the puzzle. The most important part is the general ledger of the transactions that were completed since the last block was recorded. Blocks are chained together in chronological order, thus the source of the name “blockchain”.
  14. A chain of blocks with each block referencing the block that preceded it. The most-difficult-to-recreate chain is the best block chain.
  15. Is a continuous and sequential chain of blocks that contains transaction information, agreements, and contracts within a system stored in a cryptographic form. It is virtually impossible to change the contained in the information, which ensures a high level of data reliability.
  16. The foundational technology behind the blockchain and cryptocurrency sector. It is a virtual, immutable (unchangeable), distributed store of data stored on servers around the world. This is a new way of distributing both trust and data. It is an alternative to traditional systems where a central organization holds all the data. Think of it as a chain of blocks of data, verified by consensus by any computer that chooses to participate. Each block of data containing anything from who has sent cryptocurrency to others to who owns what plot of land in a land registry. Blockchain is a distributed ledger.
Blockchain Lenght
  1. The length of the entire blockchain refers to the chain with the most combined difficulty, not the one with the most blocks.
Blocks-first Sync
  1. Synchronizing the block chain by downloading each block from a peer and then validating it.
Bloom Filter
  1. A filter used primarily by SPV clients to request only matching transactions and Merkle blocks from full nodes. Not To Be Confused With: Bloom filter (general computer science term, of which Bitcoin’s bloom filters are a specific implementation)
Bollinger Band
  1. A Bollinger Band®, developed by famous technical trader John Bollinger, is plotted two standard deviations away from a simple moving average. Essentially, it is a margin around the price of a crypto that helps indicate when a coin is overbought or oversold.
Bootstrapping
  1. The process by which a cryptocurrency moves from a state where only a few nodes participate in the consensus algorithms in the network to a fully scaled network with many more participating nodes. The fully scaled network must then remain secure under assumptions in the underlying consensus algorithms. During bootstrapping, the underlying assumptions may be relaxed.
    Reference: MIT
Breakeven Multiple
  1. The multiple of the current price by which an asset needs to appreciate in order to reach its previous all-time high.
BTFD
  1. Acronym for "Buy The F$%king Dip" A less than savoury phrase used when you're (enthusiastically) telling someone a currency has dipped to a low value and should be bought.
Bug Bounty // Bounty
  1. A reward offered for finding vulnerabilities and other issues in computer code. Often offered by cryptocurrency companies like exchanges and wallet providers to prevent hacks.
  2. A reward posted by a group or individual to incentivize certain work, behavior (such as referrals), or development.
BUIDL
  1. Originally derived from HODL, a term referring to keeping your heads down and focusing on building your product.
Bull
  1. A person that is optimistic and confident that market prices will be going up. This person is also known to be "bullish" about the market and price expectations.
Bull Market
  1. An expectation that prices within a given financial market are going to increase or have been increasing for a period of time. Bull markets are dominated by optimism, investor confidence and expectations that strong results should continue. It is difficult to predict consistently when the trends in the market might change.
Bull Trap
  1. A false market signal where the falling trend of an asset appears to be turning up, but actually is not. Long buyers can be forced to exit their positions to stop losing money.
Burning
  1. Refers to the Proof of Burn consensus algorithm. Burning coins is the action of sending them to an address where they are irretrievable. As a miner, the more coins you burn, the better chance you have of being selected to mine the next block, thus earning more rewards.
Business Logic Layer
  1. A part of code that determines the rules to be followed when doing business
C
Candidate Block
  1. A temporary block created by mining nodes using transactions from the memory pool. Each mining node tries to add this candidate block to the blockchain.
Casper
  1. Consensus algorithm that combines proof of work and proof of stake. Ethereum is going to use casper as a transition to proof of stake.
  2. Casper is an implementation of the Ethereum blockchain that promises to process more transactions per second. Ethereum used to be able to process 20 transactions a second. Bitcoin could only process 4. Visa and Mastercard can process about 20000 transactions a second. Casper is an in-between step for the Ethereum blockchain to change over from proof-of-work to proof-of-stake. It implements sharding (dividing the main Ethereum chain into smaller subcomponent chains) to provide parallel processing and increased throughput.
  3. Consensus algorithm that combines PoW and PoS. Ethereum is going to use Casper as a transition to PoS.
    Reference: BTA
Central Ledger
  1. A ledger maintained by a central agency. Also known as general ledger, a central ledger contains all the accounts for recording transactions relating to a company’s assets, liabilities, owners’ equity, revenue, and expenses.
Centralized // Centralization
  1. A form of organization whereby a single party, group, authority is in control. These systems have single points of failure. VISA, Paypal, ApplePay are examples of centralized payment systems. Centralized organizations are contrasted by decentralized systems.
  2. Centralized describes a system or organization that is controlled by one person or group. Companies are centralized organizations.
Chain
  1. The cryptographic link that keeps blocks together using a ‘hash’ function.
Chain Code
  1. In HD wallets, 256 bits of entropy added to the public and private keys to help them generate secure child keys; the master chain code is usually derived from a seed along with the master private key
Chain Linking
  1. Chain linking is the process of connecting two blockchains with each other, thus allowing transactions between the chains to take place. This will allow blockchains like Bitcoin to communicate with other side chains, allowing the exchange of assets between them
  2. Each cryptocurrency has its own blockchain – the digital ledger that stores all transaction records. Chain Linking is the process that occurs if you transfer one cryptocurrency to another. This requires the transaction to be lodged in two separate blockchains, so they must link together to achieve the goal.
Change
  1. An output in a transaction which returns satoshis to the spender, thus preventing too much of the input value from going to transaction fees. Synonyms: Change address || Change output
Chargeback
  1. In traditional payment systems (like credit cards), a customer can reverse a transaction and force the merchant to return funds. This is prevented with cryptocurrencies.
Child Pays For Parent (CPFP) // Ancestor Mining
  1. Selecting transactions for mining not just based on their fees but also based on the fees of their ancestors (parents) and descendants (children). Synonyms: Child pays for parent || CPFP || Ancestor mining Not To Be Confused With: Replace by Fee || RBF
Cipher
  1. Method of encrypting text (cyphertext) in which a cryptographic key and algorithm are applied to each binary digit in a data stream, one bit at a time.
  2. A Cipher is an algorithm used for the encryption and/or decryption of information. In common language, ‘cipher’ is also used to refer to an encryption message, also known as ‘code’.
  3. The name given to the algorithm that encrypts and decrypts information.
Circulating Supply
  1. An approximation of the number of coins or tokens that are circulating in the public market.
  2. An approximation of the number of coins or tokens that are circulating in the public market. See also: total supply and maximum supply. Market Cap = Price x Circulating Supply. Don’t be confused with total supply and max supply. They are different. If a cryptocurrency has only the circulating supply and does not have total supply or max supply, that means that cryptocurrency has no max supply limit. If the cryptocurrency has circulating supply and total supply but does not have max supply, that still means no maximum cap on that coin.
  3. The total number of coins in a cryptocurrency that is in the public tradable space is considered the Circulating Supply. Some coins can be locked, reserved or burned, therefore unavailable to public trading.
Client
  1. Software that can access blockchain on a local computer and also help process blockchain transactions. Often includes a cryptocurrency software wallet.
  2. A software program a user executes on a desktop, laptop or a mobile device to launch an application
Cloud Mining
  1. Classical cryptocurrency mining requires huge investments in hardware and electricity. Cloud mining companies aim to make mining accessible to everybody. People can simply log in to a website and invest money in the company which already has mining datacenters. The money is managed by the company and it is invested in mining equipment. Investors get a share of the revenue. The disadvantage for the user is that cloud mining has low returns compared to traditional mining.
Coin // Coins
  1. Representation of a digital asset built on a new blockchain
  2. See ‘altcoins’ for a more in depth description. A coin is it’s own currency and runs on it’s own blockchain. See ‘token’ for a differentiation from other cryptocurrency types.
  3. A coin is its own currency and runs on its own blockchain. See ‘token’ for a differentiation from other cryptocurrency types.
  4. A cryptocurrency or digital cash that is independent of any other platform, which is used as an exchange of value.
Coinbase // Coinbase Field
  1. A special field used as the sole input for coinbase transactions. The coinbase allows claiming the block reward and provides up to 100 bytes for arbitrary data. Not To Be Confused With: Coinbase transaction || Coinbase.com
Coinbase // Coinbase Transaction/Address // Generation Transaction
  1. The first transaction in a block. Always created by a miner, it includes a single coinbase. Synonyms: Coinbase transaction || Generation transaction Not To Be Confused With: Coinbase (the unique part of a coinbase transaction)
Cold Storage
  1. The offline safekeeping of private keys which allow for access to cryptocurrency funds. Typically this is done through hardware wallets, USB drives, and paper wallets.
  2. The process of moving crypto-currency ‘offline’, as a way of safekeeping your crypto-currency from hacking. There are a variety of ways to do this, but some methods most commonly used: - Printing out the QR code of a software wallet and storing it somewhere safe, such as a safety deposit box. - Moving the files of a software wallet onto a USB drive and storing it somewhere safe. - Using a hardware wallet.
  3. A way to hold or store a digital asset offline—without connection to the internet. Typical cold storage includes USB drives, offline computers, or paper wallets. Cold storage is the safest method of storing your cryptocurrency especially for wallet balances that you plan to keep untouched for a significant period of time.
CompactSize Unsigned Integer
  1. A type of variable-length integer commonly used in the Bitcoin P2P protocol and Bitcoin serialized data structures.
Composer CLI
  1. Hyperledger Fabric command line allowing for administrative tasks
Composer Rest Server
  1. Generates a rest server and associated api from a deployed blockchain
Compressed Public Key
  1. An ECDSA public key that is 33 bytes long rather than the 65 bytes of an uncompressed public key.
Confirmation Score, Confirmed Transaction
  1. A score indicating the number of blocks on the best blockchain that would need to be modified to remove or modify a particular transaction. A confirmed transaction has a confirmation score of one or higher. Synonyms: Confirmation score || Confirmations || Confirmed transaction || Unconfirmed transaction
    Reference: confirmation-score
  2. Each past block makes a transaction more irreversible because it stores them more deeply in the blockchain. Each time that happens it is called a confirmation.
  3. Means that the blockchain transaction has been verified by the network. This happens through a process known as mining, in a proof-of-work system (e.g. Bitcoin). Once a transaction is confirmed, it cannot be reversed or double spent. The more confirmations a transaction has, the harder it becomes to perform a double spend attack.
Confirmation(s)
  1. When a transaction has been confirmed, it means it has been approved by the network and permanently appended to the blockchain.
  2. A bitcoin transaction is confirmed once it has been included in a block on the blockchain by a miner. Each subsequent block added to the blockchain is another confirmation for that transaction. 6+ confirmations is generally accepted for a transaction to be finalized although 99.99% of the time Bitcoin Cash transactions can be considered final with 0 or 1 confirmation.
  3. The successful act of hashing a transaction and adding it to the blockchain. All transactions on the blockchain need to be verified by all nodes.
  4. Confirmation means that a transaction has been processed by the network and is highly unlikely to be reversed. Transactions receive a confirmation when they are included in a block and for each subsequent block. Even a single confirmation can be considered secure for low value transactions, although for larger amounts like $1000 USD, it makes sense to wait for 6 confirmations or more. Each confirmation exponentially decreases the risk of a reversed transaction.
Consensus Mechanism // Consensus Alogirthm
  1. When a transaction is made, all Nodes on the network verify that it is valid on the blockchain and if so, they have a consensus.
  2. All members of the BlockChain network are striving for it in order to ensure the information identity at all network sites.
  3. When several nodes (usually most nodes on the network) all have the same blocks in their locally-validated best blockchain. Not To Be Confused With: Social consensus (often used in discussion among developers to indicate that most people agree with a particular plan) || Consensus rules (the rules that allow nodes to maintain consensus)
  4. A fundamental problem in distributed computing is to achieve overall system reliability in the presence of a number of faulty processes. This often requires processes to agree on some data value that is needed during computation. The consensus problem requires agreement among a number of processes for a single data value. Some of the processes may fail or be unreliable in other ways, so consensus protocols must be fault tolerant. The processes must somehow put forth their candidate values, communicate with one another, and agree on a single consensus value. The bitcoin blockchain uses electricity to ensure the security of the system. It creates an economic system where you can only participate by incurring costs, Proof of work (POW). You do that for the possibility of reward/bitcoin. If you spend money, and you play fair by the rules, you get money back. If you cheat, you lose money. It doesn’t pay to cheat. This simple game theoretical equilibrium is the core of the bitcoin consensus algorithm Consensus (Bitcoin’s Process Consensus) Developers suggest bitcoin improvements/modifications, small or big, proposals on Github, Bitcointalk, Reddit, mailing lists, etc. Discussion on this level is critical to enable smooth runtime consensus transitions. Modifications with reference implementations get tested on the testnet. After successful testing developers implement the changes into the Bitcoin software. Who has a say in the consensus process?: (1) Software Developers (do the reference implementations), (2) Miners (Runtime consensus for mining blocks), (3) Exchanges (They run nodes that validate transactions), (4) Wallet companies (create transactions run on nodes), (5) Merchants (Merchant processing also through nodes)
  5. A process, encoded in software, by which computers in a network, called nodes, reach an agreement about a set of data. In the context of blockchains, the consensus algorithm is often used to agree on a block of transactions that should be appended to the blockchain.
    Reference: MIT
  6. Consensus is achieved when all participants of the network agree on the validity of the transactions, ensuring that the ledgers are exact copies of each other.
  7. When a majority of participants of a network agree on the validity of a transaction
  8. An automated mechanism that allows blockchain participants to agree on which transactions happened and in which order. This agreement is known as a trustless consensus.
  9. A process, encoded in software, by which computers in a network, called nodes, reach an agreement about a set of data.
  10. Consensus Process is a group of peers responsible for maintaining a distributed ledger use to reach consensus on the ledger’s contents.
  11. Consensus algorithms ensure convergence towards a single, immutable version of the ledger. they allow actors on the network to agree on the content recorded on the blockchain, taking into consideration the fact that some actors can be faulty or malicious. this can be achieved by various means depending on the specific needs. The most famous consensus algorithms include Proof-of-Work, Proof-of-Stake, and Proof-of-Authority.
Consensus Point
  1. A point in time when blockchain participants agree on which transactions happened and in which order. Can be based on a time interval or based on a volume of transactions.
Consensus Rules, Validation Rules
  1. The block validation rules that full nodes follow to stay in consensus with other nodes. Synonyms: Consensus rules Not To Be Confused With: Consensus (what happens when nodes follow the same consensus rules)
Consortium Blockchain
  1. A Consortium Blockchain is a blockchain where the consensus process is controlled by a pre-selected set of nodes; for example, one might imagine a consortium of 15 financial institutions, each of which operates a node and of which ten must sign every block for the block to be valid. The right to read the blockchain may be public or restricted to the participants. There are also hybrid routes such as the root hashes of the blocks being public together with an API that allows members of the public to make a limited number of queries and get back cryptographic proofs of some parts of the blockchain state. These blockchains may be considered “partially decentralized”.
    Reference:
  2. This may be a blockchain wherever the accord method is controlled by a pre-selected set of nodes; for instance, one may think a pool of fifteen monetary establishments, every of that operates a node and of that 10 should sign each block for the block to be valid. The correct to browse the blockchain is also public or restricted to the participants. There are hybrid routes cherish the basis hashes of the blocks being public beside associate degree API that enables members of the general public to create a restricted variety of queries and obtain back cryptanalytic proofs of some components of the blockchain state. These blockchains are also thought of as “partially decentralized”.
Content Delivery Network (CDN)
  1. Allows for a quick transition of assets needed to load internet content (html, js, css, etc.)
Corda
  1. Is a blockchain system for creating financial services developed by an R3 banks consortium. It has about 70 financial institutions, including Barclays, Goldman Sachs, J.P. Morgan.
Cosigner
  1. A person or entity that has partial control over a multi-signature Bitcoin wallet. To complete a send of bitcoin, a multi-sig wallet requires authorization from a certain amount of all cosigners on the wallet. The amount of authorizing cosigners required is known as ‘M of N’.
Costless Verification
  1. Recorded attributes that need to be verified securely on a blockchain can be referred to at any point on the distributed ledger at no cost.
    Reference: MIT
Cryptoanalysis (Cryptanalysis)
  1. Cryptoanalysis, or cryptanalysis, is the study of methods for obtaining the meaning (deciphering) of encrypted information, without access to the secret information (or the key) that is normally required to do so.
  2. Is the study of methods for obtaining the meaning of encrypted information, without access to the secret information that is normally required to do so.
Cryptocurrency // Crypto-Currency // Virtual Currency (VC)
  1. A scarce digital asset built on or running on top of a blockchain protocol and exchanged via that blockchain system.
    Reference: MIT
  2. Is a distributed and decentralized system for secure exchange and transfer of digital money, based on cryptographic algorithms.
  3. A type of digital currency that is generally decentralized and uses cryptography (i.e. data is converted into a format that is unreadable for unauthorized users) for added security, making it difficult to counterfeit or manipulate.
  4. A cryptocurrency is a digital currency that is secured by cryptography. One of its primary functions is to work as a medium of exchange within a peer-to-peer (P2P) economic system built on distributed ledger technology, which relies on cryptography to prevent frauds and counterfeiting. Most cryptocurrency systems are decentralized and maintained by a distributed network of computers (nodes) spread around the world.
  5. A digital currency that uses strong computer code (cryptography) and a decentralized system to allow for transactions without using middlemen like banks. AKA digital currency.
  6. A digital currency that uses cryptography to provide security and verify transactions on its network. Bitcoin is the first cryptocurrency. Unlike traditional fiat currencies, a cryptocurrency does not require a central bank or any other centralized authority to ensure security or to maintain control of money supply.
  7. A scarce digital asset defined by a blockchain protocol and exchanged via that blockchain system.
  8. A token or currency built on top of blockchain technology. This token helps capture and distribute value from users of the blockchain. You can think of Bitcoin as the first application and cryptocurrency stemming from the blockchain. Cryptocurrencies are a subset of what are known as cryptoassets.
Cryptocurrency Wallets // Wallet
  1. Software that stores private keys and monitors the blockchain (sometimes as a client of a server that does the processing) to allow users to send and receive satoshis. Synonyms: Wallet Not To Be Confused With: HD wallet (a protocol that allows all of a wallet’s keys to be created from a single seed)
  2. Is a file that contains a collection of private keys and communicates with the corresponding blockchain. Wallets contain keys, not coins. Wallets require backups for security reasons.
  3. Is a client program or web application used to manage accounts. Allows you to perform transactions from a given address and view its balance.
  4. A digital wallet is where cryptocurrencies like Bitcoin are stored. More specifically, coins are actually stored in the Blockchain itself - to which the wallet merely gives access.
  5. A file that houses a collection of private keys. It usually contains a software client which allows access to view and create transactions on a specific blockchain that the wallet is designed for. Wallets contain keys, not coins. Wallets also require backups for security reasons.
  6. A store of digital assets such as cryptocurrencies, analogous to a digital bank account. Crypto wallets can be divided into two categories: hosted wallets (e.g. wallets store on exchanges or third-party servers) and cold wallets (e.g. hardware wallets such as the Ledger Nano S, paper wallets and desktop wallets).
  7. Stores the digital assets you own.
  8. Basically, it’s the Bitcoin or cryptocurrency equivalent of a bank account. It allows you to receive cryptocurrency, store them, and then send them to others. There are two main types of wallets: software and hardware. – A software wallet is one that you install on your own computer or mobile device. Software wallets are storage for cryptocurrency that exists purely as software files on a device. Software wallets can be generated for free from a variety of sources. Read more about different software wallets, and explore some options, here. – A hardware wallet stores private keys on a secure hardware device. Hardware wallets are often regarded as the most secure way to hold crypto-currency, partly due to being ‘cold storage’ devices and having additional security features. Read more specifically on hardware wallets here!
  9. A software that manages a user’s private keys. It usually contains a software client that allows access to view and create transactions on a specific blockchain that the wallet is designed for.
    Reference: MIT
  10. A Bitcoin wallet is loosely the equivalent of a physical wallet on the Bitcoin network. The wallet actually contains your private key(s) which allow you to spend the bitcoins allocated to it in the block chain. Each Bitcoin wallet can show you the total balance of all bitcoins it controls and lets you pay a specific amount to a specific person, just like a real wallet. This is different to credit cards where you are charged by the merchant.
  11. Cryptocurrency wallets are ways of storing your private and public keys to your cryptoassets. A wallet is a safe you can access to then get your keys. Wallets allow for easier access and backups if you don’t remember your private key with techniques such as the mnemonic seed phrase, a series of 25 random words you have to input to get access to your private key. There are software wallets and hardware wallets: software wallets store your keys online, while hardware wallets use a physical device such as the Trezor to protect your private key.
Cryptographic Hash Function
  1. The cryptographic hash function is a mathematical algorithm that takes a particular input which can be any kind of digital data be it a password or jpeg file and produces a single fixed length output. Some examples of different hash function algorithms are MD5, MD4 or SHA256. The last one is used in the Bitcoin protocol. Main properties: (1) easy to compute hash value for any given message (2) infeasible to generate a message from its hash except by trying all possible input combinations(brute force attack) (3) infeasible to modify a message without changing the hash (4) infeasible to find two different messages with the same hash (5) deterministic so the same message always results in the same hash. Cryptographic hash functions have many information security applications, notably in digital signatures, message authentication codes (MACs), and other forms of authentication. They can also be used as ordinary hash functions, to index data in hash tables, for fingerprinting, to detect duplicate data or uniquely identify files, and as checksums to detect accidental data corruption
  2. Cryptographic hashes produce a fixed-size and unique hash value from variable-size transaction input. The SHA-256 computational algorithm is an example of a cryptographic hash.
  3. A function that returns a unique fixed-length string. The returned string is unique for every unique input. Used to create a “digital ID” or “digital thumbprint” of an input string.
Cryptography
  1. Cryptography is the branch of mathematics that lets us create mathematical proofs that provide high levels of security. Online commerce and banking already uses cryptography. In the case of Bitcoin, cryptography is used to make it impossible for anybody to spend funds from another user's wallet or to corrupt the block chain. It can also be used to encrypt a wallet, so that it cannot be used without a password.
  2. Refers to the process of encrypting and decrypting information. Mathematics creates codes and ciphers, in order to conceal information. Used as the basis for the mathematical problems used to verify and secure transactions on the blockchain.
  3. The practice and study of techniques for secure communication in the presence of third parties. Bitcoin and other currencies are related to cryptography insofar as they use mathematics to secure information. Within Bitcoin, cryptography creates and secures wallets, signs all transactions, and verifies each and every transaction on the blockchain.
  4. Cryptography is a method of storing and sending data in a form so that it can only be read and processed by its intended recipient.
Cryptojacking
  1. Cryptojacking is referred to as a secret use of a device to mine cryptocurrency. The first widely known attempt for cryptojacking was the torrent tracker Piratebay. They enabled an in-browser mining software so when somebody visits the website his/her computer will start mining cryptocurrency via the browser. Users started noticing the unusual behavior in their browsers and Piratebay took down the software. There have been many attempts for cryptojacking since then. The easiest way to find out if a computer is mining cryptocurrency is to check the resources monitor for unusual CPU behavior or using the debug console of your browser an look for mining scripts. Developers also released Chrome browser extensions to protect users from mining occurring on their devices.
D
DAICO
  1. A method for decentralized funding of projects. It combines ideas from Decentralized Autonomous Organizations (DAOs) and Initial Coin Offerings (ICOs). Project investors have the ability to vote and, if dissatisfied with the project's progress, could get their money back. Proposed by Vitalik Buterin, the creator of Ethereum.
  2. There are many ICOs project that doesn’t meet the requirement of surviving in the market. Also, investing in ICOs currently can be seen as gambling. DIACO is a decentralized fundraising model. It is built on top of the blockchain network such as Ethereum. It acts democratically and ensures that the token sale is made in the best interest of the investor. It uses the mechanism, “Tap.” This mechanism enables investors to do fund control. It means that the investor can invest in steps and according to certain conditions. If the conditions don’t match, then the investment will stop. On the other hand, if the condition match, the second investment will be made. The whole idea behind DAICO is to make ICOs more responsible when raising money and backup their progress with milestones. DAICO also take some features from DAO such as automation, decentralization and refund option.
Darknet
  1. A peer-to-peer layer of the internet that can only be accessed with special software. It is known as Darknet because it often involves illegal marketplaces and illicit activity.
DASH
  1. A type of cryptocurrency based on Bitcoin software but has anonymity features that makes it impossible to trace transactions to an individual and other capabilities. It was created by Evan Duffield in 2014 and was previously known as XCoin (XCO) and Darkcoin. For more information, visit the official website for DASH.
Data Mining
  1. The process of solving cryptographic problems using computer hardware to add newly hashed blocks to a public blockchain such as bitcoin. In fulfilling this function, successful data miners keep the blockchain actively recording transactions and, as an incentive, are awarded newly minted bitcoins for their trouble.
DDos Attacks
  1. A denial-of-service attack is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to the Internet.
Death Spiral Scenario
  1. A bitcoin death spiral is basically a scenario where a large number of miners decide to stop mining at nearly the same time because the activity is no longer profitable for them. Bitcoin’s protocol rules are structured in a way where a new block of transactions should be mined roughly every ten minutes. Blocks will be found more quickly if more miners throw hashpower at the network (perhaps due to a higher bitcoin price), and blocks will be found less frequently as miners start to leave the network (perhaps due to a falling bitcoin price). The idea is that so many miners would decide to leave the network after a sharp price decline (or for some other reason) that the network would effectively grind to a halt and no new transactions could be made.
Decentalized Initial Coin Offering (DICO)
  1. A dICO is a new approach to an Initial Coin Offering brought to market by Komodo, which utilizes a decentralized approach, detaching coins from the blockchain that they are built on. This has been launched by Komodo, who also claim that all coins created on their platform can natively interact with any other supported coins, with Komodo serving as a bridge within a network of blockchains. All currencies created using Komodo as a dICO will operate independently, which means that not all transactions will be recorded on the parent blockchain, which would theoretically help to reduce blockchain bloat.
Decentralised Autonomous Organizations // DAO // Decentralized Autonomous Organization
  1. Decentralised Autonomous Organizations can be thought of as corporations that run without any human intervention and surrender all forms of control to an incorruptible set of business rules.
  2. In general, a system of hard coded rules that define which actions an organization will take. The DAO may also refer specifically to the DAO Organization that was instantiated on the Ethereum blockchain.
  3. fully automated business entity (FAB), or distributed autonomous corporation/company (DAC) is a decentralized network of narrow-AI autonomous agents which perform an output-maximizing production function and which divides its labor into computationally intractable tasks (which it incentivizes humans to do) and tasks which it performs itself. It can be thought of as a corporation run without any human involvement under the control of an incorruptible set of business rules. These rules are typically implemented as publicly auditable open-source software distributed across the computers of their stakeholders. A human becomes a stakeholder by buying stock in the company or being paid in that stock to provide services for the company. This stock may entitle its owner to a share of the profits of the DAO, participation in its growth, and/or a say in how it is run…
  4. A decentralized autonomous organization is an organization that is run through rules encoded as computer programs called smart contracts.
  5. An investor-funded and directed venture capital crowd-fund built on the Ethereum network that was hacked in June 2016 and subsequently shut down.
  6. Decentralised Autonomous Organizations can be thought of as corporations that run without any human intervention and surrender all forms of control to an incorruptible set of business rules. Instead of a hierarchical structure managed by a set of humans interacting and controlling property through a legal system, a Decentralized Organization relies on protocols set in code and enforced via blockchain. A Decentralized Autonomous Organization takes it one step further and exists autonomously as an entity living on the internet.
  7. DAOs or decentralized autonomous organizations are a collective grouping in which smart contracts make choices. The entire organization is run on the blockchain. Shareholders buy tokens that give them the right to vote on future decisions.
Decentralization
  1. A measure of how much authority is held by a central holder. You can argue that blockchains are naturally more decentralized than other methods of distributing data because there is (at least in public chains) no gatekeeper on who can join: as long as you have the computing power, you can participate in the blockchain. Instead of all of your data residing in one central provider (ex: Equifax), it now sits and is processed and verified by a global network of computers. Decentralization is an ideal of the blockchain community. However, it has not been perfectly achieved. For example, the mining pools that mine most of Bitcoin are mostly based in China: a consortium of these mining pools might decide to do what is called a 51% attack. They would use their assembled computing power to change the rules of the blockchain and facilitate conditions such as “double spend”: the ability to infinitely spend the same block of cryptocurrencies, essentially creating wealth out of nothing. The control of mining resources is very centralized.
Decentralized
  1. The structure where a network or service is distributed over a large group of people or operations, such as in a peer-to-peer network. The advantage of a decentralised network is the absence of a single point of failure. The Internet is a good example of a decentralised global network of computers. Terminology-wise however, a decentralised structure is slightly different from a distributed structure.
  2. A decentralized system is one that has no single head or group that completely controls it. In other words, there is a more or less even distribution of power among multiple parties rather than centralized control by one or a few parties. This can take place in a computer network, a distribution network, or even a political system.
  3. Decentralized Exchange A peer-to-peer exchange that allows users to buy and sell cryptocurrency and other assets without the control or fees of a central authority. Unlike central services like CoinBase. Decentralized Organization A smart-contract based organization that uses automated rules to run without a central authority. Funding, voting, and more are all handled via platforms like Ethereum.
  4. A state where there is no central control, power or function, or in reference to infrastructure, no central point of failure. Blockchains are politically decentralized (no one controls them) and architecturally decentralized (no infrastructural central point of failure) but they are logically centralized (there is one commonly agreed state and the system behaves like a single computer).
  5. A form of organization which does not require any single party, group, or authority to control services. Bitcoin is a decentralized network because no company, government, or individual created or is in control of it. Bitcoin’s governance relies on the community and its code is open-source.
  6. The concept of a shared network of dispersed computers (or nodes) that can process transactions without a centrally located, third-party intermediary.
  7. Decentralized is defined as a type of system where elements are spread out by some means, with decisions made from many points, and independence is preserved across the network. Decentralization is actually a combination of 3 parts making up a triangle. Structure: A system located in multiple places across a space, is a decentralized structure. Management: A system managed by my many equally powerful units, with no single ruling unit is a decentralized management. Independence: A system made up of independent units working together for a common purpose is a decentralized independence. Here are some examples of decentralized systems: The American-English language is a decentralized structure because it is spoken by millions of people across the globe. It is a decentralized management because every person can make up their own mind as to how they speak English. There is independence because you can speak English even if everyone around you speaks a different language. A forest is a decentralized structure because it is made up of thousands and thousands of trees each located some distance from each other. It has a bit of decentralized management because each tree grows in its own way. It has independence because tree can survive on its own despite the fact that they are all surviving as a group. Species of life are decentralized structures because each life form is located in its own space, separate from others. It is a decentralized management because each one manages its own livingness. It has independence because each life form can live on its own without others, to some degree. Decentralized systems have some advantages including: Resistance to Attack: If several units in the decentralized system are attacked, the system will stay up. Resistance to Problems: If several units in the decentralized system have problems or bugs, the system will remain active. Resistance to Manipulation: If several units in the decentralized system join together with harmful intentions, the system will remain intact and active.
Decentralized Applications // Decentralized Apps // dApps || ÐApps || Dapp || DApp || DApps
  1. Is an application that is open source, operates autonomously, has its data stored on a blockchain, incentivized in the form of cryptographic tokens and operates on a protocol that shows proof of value.
  2. Decentralized applications, or applications that exist on a decentralized network. They often use smart contracts in their back-end code, and are common in the Ethereum network.
  3. Applications that run without the control of a central authority (like a software company or government). Ethereum is the first and largest decentralized application platform.
  4. For an application to be considered a Dapp or decentralized application it must meet the following criteria (1) Application must be completely open-source, it must operate autonomously, and with no entity controlling the majority of its tokens. The application may adapt its protocol in response to proposed improvements and market feedback, but all changes must be decided by consensus of its users. (2) Application data and records of operation must be cryptographically stored in a public, decentralized blockchain in order to avoid any central points of failure. (3) The application must use a cryptographic token (bitcoin or a token native to its system) which is necessary for access to the application, and any contribution of value from miners/farmers should be rewarded with the application’s tokens. (4) The application must generate tokens according to a standard cryptographic algorithm acting as a proof of the value nodes are contributing to the application (Bitcoin uses the Proof of Work Algorithm)
  5. Applications that run on a P2P network of computers rather than one central computer. This allows the software to run on the internet without being controlled by a single entity.
  6. A type of software program that runs on a decentralized P2P network rather than on a single computer. Although similar, it differs from smart contracts as it can have any number of participants on all sides of the market and it does not have to be financial. Ethereum is a popular development platform for creating dApps.
  7. Dapps are a new type of architecture being used in the blockchain. Dapps store data and source code in a decentralized manner that is distributed on the blockchain. The biggest advantage to this structure is that a Dapp ensures the blockchain application is always online and is not reliant on a single server’s availability.
    Reference: MIT
  8. A decentralised application (dApp) is an application that is open source, operates autonomously, has its data stored on a blockchain, incentivised in the form of cryptographic tokens and operates on a protocol that shows proof of value. For an application to be considered a dApp or decentralized application it must meet the following criteria (1) Application must be completely open-source, it must operate autonomously, and with no entity controlling the majority of its tokens. The application may adapt its protocol in response to proposed improvements and market feedback, but all changes must be decided by consensus of its users. (2) Application data and records of operation must be cryptographically stored in a public, decentralized blockchain in order to avoid any central points of failure. (3) The application must use a cryptographic token (bitcoin or a token native to its system) which is necessary for access to the application, and any contribution of value from miners/farmers should be rewarded with the application’s tokens. (4) The application must generate tokens according to a standard cryptographic algorithm acting as a proof of the value nodes are contributing to the application (Bitcoin uses the Proof of Work Algorithm).
  9. A decentralized application is a specific type of app that serves a specific purpose within a blockchain network. It must be open-source, autonomous, and it must make changes to the underlying software via consensus from its users. It must store all its data on a public blockchain, which is auditable by the public, and it must generate tokens and be accessible via those same tokens. DApps seem like regular web applications. Client-side, the same mechanism is in play, but server-side (or the back-end), data and control are distributed among a network of P2P (peer-to-peer) nodes and smart contracts rather than a centralized set of servers and server code.
Decentralized Autonomous Cooperative (DAC)
  1. An organization that is controlled by shareholders rather than a central authority.
Decentralized Exchange
  1. An exchange which does not require users to deposit funds to start trading and does not hold the funds for the user. Instead, users trade directly from their own wallets.
Deflation
  1. When the demand for a particular cryptocurrency decreases, bringing down the price of its economy.
Delegated Proof of Stake (DPoS)
  1. DPOS is a variation of POS. With DPOS, coin holders can use their balance to elect a list of nodes to be possibly allowed to add new blocks of transactions to the blockchain. Coin holders can also vote on changing the network parameter. POS is more like winning a lottery, while DPOS gives all coin holders more influence and ownership in the network.
Depth Chart
  1. This graph plots the requests to buy (known as bids) and the requests to sell (known as asks) on a chart. Because you can put a Limit Order on your buy or sell transaction, the Depth Chart shows the crossover point at which the market is most likely to accept a transaction in a timely fashion. It also shows if there are any significant Buy Walls or Sell Walls in play.
Design Goals
  1. Design goals refer to the first step in the Blockchain 3 layer model. They are set of concepts or properties that you wish your smart contract to have. These include Distribution, Decentralization, Immutability and Peer to Peer.
Deterministic Wallet
  1. This type of wallet is created by producing multiple keys from a seed. If you lose this wallet, your wallet key can be recovered from the seed. Plus, when you make transactions, instead of producing new keys each time, you use variations from the seed, which makes it more transferable and easier to store.
Difficulty // Mining Difficulty
  1. Mining difficulty measures how hard it would be to find the next Bitcoin block. Every proof of work consensus algorithm has a mining difficulty which is also adjustable. Depending on how many miners join the network the difficulty might rise or fall. The aim of the difficulty is to keep the block times even and make the network secure. The average time for finding a Bitcoin block is set for 10 minutes. Litecoin is set for 2.5 minutes.
  2. How difficult it is to find a block relative to the difficulty of finding the easiest possible block. The easiest possible block has a proof-of-work difficulty of 1. Synonyms: Difficulty || Network difficulty Not To Be Confused With: Target threshold (the value from which difficulty is calculated)
  3. In Proof-of-Work mining, is how hard it is to verify blocks in a blockchain network. In the Bitcoin network, the difficulty of mining adjusts verifying blocks every 2016 blocks. This is to keep block verification time of ten minutes.
  4. In Bitcoin terms, this is a measure of how difficult it is to mine a block of bitcoin, which is directly considered as how difficult it is for miners to generate a new block of transactions on the blockchain. The Bitcoin network adjusts this difficulty once every 2,016 blocks, a period which roughly spans about 2 weeks, in order to keep the rate of new blocks generated consistent at approximately 10 minutes. Difficulty is a function of how much hashing power has been deployed by the network of miners Hence, it is also adjusted as the number of miners go up and down. The formula for difficulty is given by difficulty = difficulty_1_target / current_target, where target is a 256-bit number. For the current difficulty rate in real time, see the Blockchain.info difficulty chart.
  5. This refers to how easily a data block of transaction information can be mined successfully. In Proof-of-Work mining, is how hard it is to verify blocks in a blockchain network. In the Bitcoin network, the difficulty of mining adjusts verifying blocks every 2016 blocks. This is to keep block verification time at ten minutes. Mining difficulty measures how hard it would be to find the next Bitcoin block. Every proof of work consensus algorithm has a mining difficulty which is also adjustable. Depending on how many miners join the network the difficulty might rise or fall. The aim of the difficulty is to keep the block times even and make the network secure. The average time for finding a Bitcoin block is set for 10 minutes. Litecoin is set for 2.5 minutes.
  6. When someone refers to difficulty in the cryptocurrency space, they are referring to the cost of mining in that moment in time. The more transactions that are trying to be confirmed at any single moment in time, divided by the total power of the Nodes on the network at that time, defines the difficulty. The higher the difficulty, the greater the transaction fee – this is a fluid measurement that moves over time.
  7. a number defining how difficult it is to hash a new block. As computing power for hashing increases, the difficulty level increases.
  8. How difficult it is to find a block relative to the difficulty of finding the easiest possible block. The easiest possible block has a proof-of-work difficulty of 1. Synonyms: Difficulty || Network difficulty Not To Be Confused With: Target threshold (the value from which difficulty is calculated)
  9. The best way to think about Bitcoin difficulty is to view it as the maximum amount of computing power it will take to find a particular block reward. The difficulty number is what helps keep the Bitcoin block time at around ten minutes. As more hashing power is added to the network from different computers around the world, the difficulty of finding a block needs to be adjusted accordingly. If there was no mechanism for regulating the amount of hashing power it will take to mine a particular block, then it would be impossible to effectively secure the blockchain. How is Bitcoin Difficulty Regulated? The difficulty of mining a particular Bitcoin block changes over time to make sure that it does not become too easy or too difficult to mine bitcoins. As more hashing power is added to the Bitcoin network, it becomes more difficult to mine bitcoins. Bitcoin difficulty is recalculated every 2016 blocks, which usually turns out to be roughly every two weeks. After every 2016 mined blocks, the Bitcoin difficulty is readjusted based on the speed at which the previous 2016 blocks were mined. It is possible for Bitcoin difficulty to decrease, but this has only happened on rare occasions where the hashing power on the network has also decreased. How is Bitcoin Difficulty Calculated? When Satoshi started to mine the first blocks on the Bitcoin blockchain, the difficulty of mining those blocks was 1. The Bitcoin difficulty can never drop below 1. The timestamps of every 2016 blocks are compared to figure out whether or not the difficulty of finding the next 2016 blocks will need to be altered. These adjustments are made to make sure it always takes roughly two weeks to find the next 2016 blocks. For example, the Bitcoin difficulty would need to be increased by 40% if it took ten days to mine the last 2016 blocks. Using Bitcoin Difficulty in Mining Expectations Bitcoin difficulty is one of the key factors to consider when investing in any kind of Bitcoin mining system. Although you can use the current difficulty level to estimate your total share of block rewards until the next difficulty adjustment, it becomes quite difficult to correctly predict what the Bitcoin difficulty will be only a few months into the future. Adjustments made to the Bitcoin difficulty over time are one of the main reasons that waiting for Bitcoin hardware deliveries have been such a disaster in the Bitcoin community. The difficulty of mining on the Bitcoin network tends to increase over time, so even a few weeks can cut the project profits earned from a particular piece of mining hardware by more than 25%. One of the main benefits of mining bitcoins on a platform such as CEX.IO is that you’re able to get instant delivery of your share of mining power on the GHash.IO mining pool.
Digital Commodity
  1. These goods may be a scarce, electronically transferrable, and intangible, with a value.
  2. Is a scarce, electronically transferrable, intangible, product or service with a market value.
  3. An intangible, hard to get asset that is transferred electronically, and has a certain value.
Digital Identity
  1. Is an online or networked identity adopted or claimed in cyberspace by an individual, organization, or electronic device.
  2. Is information about an entity used to represent an external agent. This is placed online or networked identity adopted or claimed in cyberspace by an agent, which can be an individual, organization, application, or electronic device. A Digital Identity is comprised of characteristics, or data attributes, such as the following: Username Password Date of Birth Social Security Number Medical History Online Search Activities Electronic Transactions Purchasing history or behavior Email address URL Domain
  3. This is an internet or networked identity adopted or claimed on the internet by a private, organization, or device.
Digital Signature
  1. A mathematical scheme used for presenting the authenticity of digital assets
  2. A digital code generated by public key encryption that is attached to an electronically transmitted document to verify its contents and the sender’s identity.
  3. Private keys are used for signing transactions. Each time a transaction is sent over the blockchain it gets signed by the user’s private key. The signed transaction is broadcasted over the network together with the corresponding public key. Each miner is able to verify the signature by verifying the signature with the public key. The signature ensures that only the owner of the account can move money or assets out of the account.
  4. Is a code generated by a public key cryptosystem. That is a combination of public and private cryptographic keys that are used to verify the transaction authenticity and sender identification. The code is attached to electronic documents for checking their content and sender identity verification.
  5. One of two functions involved in public-key cryptography (see definition). A digital signature is a pair of cryptographic algorithms that can be used to authenticate messages sent over public channels. The signing algorithm takes the private key and the message as input and produces an authentication tag. The verification algorithm takes the public key, the message, and the tag as input, and verifies that the message was signed by the corresponding private key.
    Reference: MIT
Directed Acyclic Graph (DAG)
  1. If we consider Bitcoin to be Blockchain 1.0, the waves of Ethereum to be Blockchain 2.0, Directed Acyclic Graph (DAG) may become Blockchain 3.0. In Graph theory, DAG is a finite directed graph with no directed cycles. It is a well-known data structure in computer science and often used to solve problems such as finding the best route, data process. Bitcoin has been facing the bottleneck of inefficiency due to its POW protocol. One block takes 10 minutes to be created, and blocks cannot be created simultaneously. With DAG, transactions can be running on different chains simultaneously. This might be the future of instant transactions with a minimum transaction fee. ITC (IoT Chain), a project in China, is built on DAG and can process over 10,000 transactions per second.
Distributed (Network)
  1. Also know as peer-to-peer (p2p). A distributed network does require users to connect to any central server or entity. In a distributed network, users connect directly to each other. Bitcoin is a distributed network that does not have any central processing entity.
  2. A type of network where processing power and data are spread over different nodes in the network rather than having a centralised data center. This provides a single data communication network, which can be managed jointly or separately by each network. The distributed network often also distributes communication as well as processing.
  3. Distributed is defined as a type of computer system that is run simultaneously by many computers but run as a single system with the benefit of greater performance, capability, and reliability. There are 3 separate goals a distributed computing system may be designed for: Performance: Be able to do a lot of intense computing in a short time. Scalability: Be able to service many people, in many locations at the same time. Reliability: Be able to service people even if one fails or is unavailable.
Distributed Consensus
  1. Collective agreement by various computers in a network and allows it to work in a decentralized, P2P manner without the need of central authority to deter dishonest network participants. Bitcoin uses proof of work to maintain consensus in its peer-to-peer network. Nodes in the bitcoin network attempt to solve a cryptographic proof-of-work problem, where probability of finding the solution is proportional to the computational effort, in hashes per second, expended, and the node that solves the problem has their version of the block of transactions added to the peer-to-peer distributed timestamp server accepted by all of the other nodes. As any node in the network can attempt to solve the proof-of-work problem, a Sybil attack becomes unfeasible unless the attacker has over 50% of the computational resources of the network.
Distributed Ledger Technology (DLT) // Distributed Ledgers
  1. Is a consensus of replicated, shared, and synchronized digital data geographically spread across multiple sites, countries, or institutions. There is no central administrator or centralized data storage.
  2. A distributed ledger is a database that is consensually shared and synchronized across network spread across multiple sites, institutions, or geographies. It allows transactions to have public witnesses, thereby making a cyberattack more difficult. In general, a blockchain is only one of the many types of data structures that provide secure and valid achievement of distributed consensus (see, for example, R3 Corda for a non-blockchain-based distributed ledger technology).
  3. Distributed ledger is defined as a system of independent computers that are simultaneously recording data. With distributed ledger technology, identical copies of the recording are kept by each computer. We can define a distributed system, as one where all computers work independently toward the same goal as one large system. We can define a ledger as a book used to record transactions (money in, money out). However, distributed ledger technology has evolved beyond recording transactions so that it can record any data. With distributed ledger technology, there is no central authority maintaining the system. Instead, updates to the ledger are independently created and then voted on. Once an agreement regarding the update has been reached, a recording is made in the ledger. The latest version of the ledger, with the new recording, is then saved to each computing system and the process repeats itself. The first type of distributed ledger technology is called the blockchain.
  4. This is an analogy often made about blockchains. Instead of a centralized bank ledger, blockchains offer the promise of distributing balances throughout a network of computer servers. You aren’t going to a single bank to store where you send your value — instead, you are going to a decentralized network of peers. Distributed ledgers aren’t a new concept: the island of Yap used individual tables as early as 500 AD. They yelled at one another whenever they made a new transaction. Blockchains and cryptocurrencies offer the global, virtual network equivalent of that system.
  5. Distributed ledgers are ledgers in which data is stored across a network of decentralized nodes. The distribution allows for records to be independently constructed and held by every node, and not communicated to nodes held by a central authority like traditional centralized ledgers. Every single node on the network processes every transaction, coming to its own conclusions and then “voting” on those conclusions to make certain the majority agree with the conclusions. A distributed ledger does not have to have its own currency and may be permissioned and private. Distributed ledger data can be either “permissioned” or “unpermissioned” to control who can view it.
  6. A type of computer database that is stored on many private computers at the same time, instead of central company servers. Blockchains are also known as distributed ledgers.
  7. A database held and updated independently by each participant (or node) in a large network. The distribution is unique: records are not communicated to various nodes by a central authority.
  8. Distributed ledgers are ledgers in which data is stored across a network of decentralized nodes. A distributed ledger does not have to have its own currency and may be permissioned and private.
  9. Distributed ledger technology (DLT)/ A system, most commonly a blockchain, for creating a shared, cryptographically secured database.
  10. Another term for a blockchain. Distributed ledgers are ledgers in which data is stored across a network of decentralized nodes. A distributed ledger does not have to have its own currency and may be permissioned and private.
    Reference: MIT
Divergence
  1. Divergence occurs when the price of an asset and a certain indicator (e.g. MACD, RSI) are heading in opposite directions.
Do Your Own Research (DYOR)
  1. DYOR stands for “Do Your Own Research.” It is aimed at investors or newbies who are told to do their own research and not rely on anyone else for their financial or investment decisions. It is a slang word that is heavily used in cryptocurrency community especially when someone shares their opinion. Cryptocurrency is a volatile platform and hence requires the need for DYOR everytime an investor decides to invest. Investing in cryptocurrency is very risky, DYOR!.
  2. A valuable piece of advice. It's always wise to research a coin or token yourself instead of following what others say.
Double Spending // Double Spend
  1. Double-spending occurs when a sum of money is spent more than once.
    Reference: MIT
  2. This refers to a state of affairs, within the Bitcoin network, wherever somebody tries to send a bitcoin group action to 2 completely different recipients at an identical time. However, once a bitcoin group action confirm, it makes it nearly not possible to double pay it. A lot of confirmations that a specific group action has, the more durable it becomes to double pay the bitcoins.
  3. If a malicious user tries to spend their bitcoins to two different recipients at the same time, this is double spending. Bitcoin mining and the block chain are there to create a consensus on the network about which of the two transactions will confirm and be considered valid.
  4. Double-spending is the result of successfully spending some money more than once. Bitcoin is the first to implemented a solution in early 2009 which protects against double spending by verifying each transaction added to the blockchain to ensure that the inputs for the transaction had not previously already been spent
  5. A transaction that uses the same input as an already broadcast transaction. The attempt of duplication, deceit, or conversion, will be adjudicated when only one of the transactions is recorded in the blockchain.
  6. A problem in which somebody fraudulently sends digital money to two different receivers (even though they only have enough for one transaction). Bitcoin solves this issue.
  7. Double-spending is the result of successfully spending some money more than once. Bitcoin is the first to implemented a solution in early 2009 which protects against double spending by verifying each transaction added to the blockchain to ensure that the inputs for the transaction had not previously already been spent
  8. Double spending occurs when a sum of money is spent more than once. This is a problem unique to digital currencies because digital information can be reproduced relatively easily. Double Spending refers to a scenario, in the Bitcoin network, where someone tries to send a bitcoin transaction to two different recipients at the same time. However, once a bitcoin transaction is confirmed, it makes it nearly impossible to double spend it. The more confirmations that a particular transaction has, the harder it becomes to double spend the bitcoins. Double-spending is the result of successfully spending some money more than once. Bitcoin is the first to implement a solution in early 2009 which protects against double spending by verifying each transaction added to the blockchain to ensure that the inputs for the transaction had not previously already been spent. Hackers have tried to get around the Bitcoin verification system by using methods such as out-computing the blockchain security mechanism, or using a double-spending technique that involves sending a fraudulent transaction log to a seller and another to the rest of the Bitcoin network. These ploys have met with only limited success. In fact, most Bitcoin thefts so far have not involved double-counting, but rather have been due to users storing bitcoins without adequate safety measures.
  9. Is an attempt to spend money twice. This happens when someone carries out a financial transaction and then conducts another transaction with the same money.
  10. Refers to a scenario, in the Bitcoin network, where someone tries to send a bitcoin transaction to two different recipients at the same time. However, once a bitcoin transaction is confirmed, it makes it nearly impossible to double spend it. The more confirmations that a particular transaction has, the harder it becomes to double spend the bitcoins.
  11. Double spending occurs when a sum of money is spent more than once.
  12. When a given amount of coins are spent more than once. Usually as a result of a race attack or a 51% attack.
Dust Transaction
  1. Sometimes people will look to slow the network by deliberately flooding it with minor transactions that are incredibly small. These minuscule amounts are referred to as a Dust Transaction.
E
Eclipse Attack
  1. When the majority of peers on the network are malicious and monopolize the network in order to prevent specific nodes from receiving information from honest nodes.
EMV
  1. The Ethereum Virtual Machine (EVM) is a simple but powerful, Turing complete 256bit Virtual Machine that allows anyone to execute arbitrary EVM Byte Code. The EVM is part of the Ethereum Protocol and plays a crucial role in the consensus engine of the Ethereum system. It allows anyone to execute arbitrary code in a trust-less environment in which the outcome of an execution can be guaranteed and is fully deterministic. Executing code within the Ethereum network takes time, and execution is generally pretty slow compared to other VMs.
  2. The Ethereum Virtual Machine (EVM) is a Turing complete virtual machine that allows anyone to execute arbitrary EVM Byte Code. Every Ethereum node runs on the EVM to maintain consensus across the blockchain.
Encryption
  1. The use of mathematics and computer code (cryptography) to protect sensitive data like digital wallets, private keys, and personal information from unauthorized access.
  2. Conversion of information or data into a secure code in order to prevent unauthorised access to the information or data.
Enterprise Ethereum Alliance (EEA)
  1. A group of Ethereum core developers, startups, and large companies working together to commercialize and use Ethereum for different business applications.
  2. The industry’s first global standards organization to deliver an open, standards-based architecture and specification to accelerate the adoption of Enterprise Ethereum.
Enum
  1. Short for ‘enumeration’ - a fixed list of possible values. The list of US states could be considered an enum.
  2. An address value type.
EOA
  1. Externally Owned Account
Equity Tokens
  1. A token that represents an ownership interest in a company. Equity tokens work similar to traditional stocks and may include voting rights. Equity tokens are also used to represent ownership rights in company debt. They are designed to improve transparency and liquidity (the ability to buy and sell the equity when investors need it).
ERC
  1. Stands for "Ethereum Request for Comments," and is a summation of proposed improvements to the Ethereum system.
ERC 1155 // ERC-1155 || ERC1155
  1. An Ethereum based hybrid of fungible and non-fungible tokens. Used for collectables in games, created by the Enjin team.
ERC 165 - which supports ERC 721 // ERC-165 || ERC165
  1. This is really a standard for a method, instead of tokens. However, it’s important for another token standard, ERC 721, which can’t be implemented without it. More on ERC 721 later. A smart contract needs to interact with crypto tokens. While all contracts can interact with ERC 20 tokens, it’s different for other ERC standards for tokens, like ERC 721. Smart contracts need to implement specific interfaces to interact with tokens following other standards. Now, the Ethereum development community needs to know which interfaces a smart contract implements, and there is a need to publish this information. This is because they need to know in which ways they can interact with that contract. There wasn’t a standard method to detect interfaces that a smart contract uses, and to publish it. ERC 165 standardizes a method for this, besides standardizing the identification of interfaces.
ERC 20 Standard // ERC20 || ERC-20
  1. A set of standards based on the Ethereum blockchain. ERC20 allows anybody to create a token built on top of Ethereum’s blockchain. It is the basis of the initial coin offering craze and the advent of new “altcoins”.
  2. A technical standard used on the Ethereum Blockchain. ERC stands for Ethereum Request for Comments. '20' is the unique proposal ID number.
  3. The standard to which each Ethereum token complies. It defines the way that each token behaves so that transactions are predictable. Other cryptocurrencies also use the ERC-20 standard, piggybacking on the Ethereum network in the process.
  4. ERC 20 is the most popular token standard and most ICOs that have issued their tokens on the Ethereum platform have used it. If you are an Ethereum developer, you can code your smart contracts assured with the knowledge that it can easily interact with ERC 20 tokens. Just like the Ethereum developers needn’t know anything more about that token, wallet developers can also breathe easy! They don’t need to do any custom development or integration steps to ensure the token works with their wallet app. It’s a fungible token standard. This means that two coins of any token built on it have the same value at a given point in time. Take the example of LockChain, the decentralized 0%-commission travel marketplace. Their LOC token follows ERC 20, and 1 LOC token has exactly the same value as another LOC token at a certain point in time.
  5. ERC-20 is a type of token standard specifically for the Ethereum blockchain, which ensures the tokens perform in a predictable way by defining a common list of rules for all Ethereum tokens to follow. This allows the tokens to be easily exchangeable and able to work immediately with decentralized applications that also use the ERC-20 standard. Most tokens released through ICOs are compliant with the ERC-20 standard.
ERC 223 – to prevent loss of ERC 20 tokens // ERC-223 || ERC223
  1. If you send ERC 20 tokens to smart contracts that can’t handle tokens, this action burns the tokens, and you can’t recover them. ERC 223 proposes to prevent this. Developers can either accept or decline tokens arriving at their smart contract addresses. It specifies functions that a contract can code so that if it can’t accept token, the transfer will fail. This doesn’t burn any token. While ERC 223 intends to save wealth lost accidentally, it’s not yet implemented. No tokens use it, and crypto exchanges may not be prepared for this standard. Also, Ethereums’ move to implement ‘Ethereum Name Service’ (ENS) will make such transactions very rare. Hence we need to see if the Ethereum community will implement this proposal.
ERC 621 – to modify the total token supply // ERC-621 || ERC621
  1. An extension to ERC 20, this standard is to increase or decrease total token supply using two functions, i.e. ‘increaseSupply’, and ‘decreaseSupply’. The proposal recommends that only contract owner or trusted users should use them. Cryptocurrencies are mathematical money, unlike fiat currencies where central banks can increase or decrease the supply. Total token supply is one among many factors determining token appreciation and impacts the economics of a token. This proposal is a draft, and we need to see whether the Ethreum community will implement it, given the wide-ranging impact.
ERC 721 – the standard for non fungible tokens // ERC-721 || ERC721
  1. Do you want to develop an Ethereum DApp game like CryptoKitties? Axiom Zen, a Vancouver, British Columbia, Canada based company launched it in the last week of November 2017, and by the first week of December, it went viral! Players spent millions of US dollars worth of Ether on it within a week. In this game, players can buy, sell, and breed cute digital kittens. With the transparency that the Ethereum blockchain platform offers, everyone can see the rules of the game, hence the competition is fair. If you can breed rare breed of digital kittens, you can get a higher price for them. The reason I discussed CryptoKitties here is that every digital kitten in this game is a unique digital collectible. Each one commands a different price, hence you can’t use ERC 20 standard for the kittens. You need a non fungible token standard, and that’s what ERC 721 is. There are other use cases too for non fungible tokens, for e.g. power distribution sector can use them. A smart contract that will interact with ERC 721 tokens must implement a separate interface, and hence it needs to follow the ERC 165 standard.
  2. An Ethereum based non-fungible token. ERC stands for Ethereum Request for Comments. '721' is the unique proposal ID number. Created by the Cryptokitties team.
ERC 777 – to reduce friction in crypto transactions // ERC-777 || ERC777
  1. While invoking a smart contract, after the first transaction, the ERC 20 standard requires another transaction to verify whether the criteria are met. The smart contract is invoked only after this. This increases the number of transactions, effectively causing friction. ERC 777 is a proposed standard that includes a function to identify receipt of tokens and start a smart contract immediately after the first transaction. While lowering the transaction overhead, it also allows a user to reject incoming tokens from a blacklisted address. Blacklisting of an address can be for various reasons such as hacking or illegal activities. An ability to decline payment from such an address improves security position of an Ethereum DApp. ERC 777 upholds all strengths of ERC 20. The Ethereum community hasn’t implemented it yet.
ERC 827 – enables token transfer for a 3rd party to spend it // ERC-827 || ERC827
  1. It’s another extension of ERC 20, however, it intends to resolve the problem that ERC 223 tries to solve, in an enhanced manner. If this standard is implemented, a token holder can transfer token while also approving a 3rd party to spend it. With this ERC standard, wallets and exchanges can reuse tokens, because both parties agree on specific criteria for a 3rd party to spend a dynamic amount. The Ethereum community hasn’t implemented it yet.
ERC 865 – to help those who are new to crypto // ERC-865 || ERC865
  1. As a user new to crypto, when you try to transfer Ethereum-based token, you suddenly find that you need to pay miner fees in Ether. It increases friction for you. Among ERC standards developers in the Ethereum community has proposed, ERC 865 intends to make it easy for new crypto users. It proposes using the token to pay the miner fees as well. It’s a draft proposal.
ERC 884 – to tokenize stock //ERC-884 || ERC884
  1. Recent legislation in the US state of Delaware now allows companies to use blockchain to maintain share registries. Among proposed ERC standards, ERC 884 intends to take advantage of it. It will designate each token as a share of a corporation incorporated in the Delaware state. To comply with regulations, ERC 884 also includes the following: Identity verification and mandatory whitelisting of token holders; The corporation can prepare a list of shareholder according to the regulatory requirements; Recording of information regulators mandate; Record transfer of shares according to regulatory requirements; Only whole value of tokens, i.e. no partial value; Shareholders that lost their private key or tokens must get them back in a new address. Implementing ERC 884 requires an off-chain database for various ‘Know Your Customer’ (KYC) requirements. It’s still a draft proposal.
Escrow
  1. A transaction in which a spender and receiver place funds in a 2-of-2 (or other m-of-n) multisig output so that neither can spend the funds until they’re both satisfied with some external outcome. Synonyms: Escrow contract
  2. Escrow is a bond, deed, or other document kept in the custody of a third party, taking effect only when a specified condition has been fulfilled.
Ether (ETH)
  1. A type of cryptocurrency that is used for operating the Ethereum platform and is used to pay for transaction fees and computational tasks. In the platform, transaction fees are measured based on the gas limit and gas price and ultimately paid for in Ether.
  2. Is the minimum unit of Ethereum, the second cryptocurrency after bitcoin by capitalization in the world.
  3. Is the native token of the Ethereum blockchain which is used to pay for transaction fees, miner rewards and other services on the network.
  4. Ether (ETH) is the native token of the Ethereum blockchain, and the premier cryptocurrency that is used for operating the Ethereum platform. It is used to pay for transaction fees, miner rewards, and computational tasks. In the platform, transaction fees are measured based on the gas limit and gas price and ultimately paid for in Ether.
  5. The digital currency of the Ethereum network. Ether is used to pay the transaction and processing fees of Ethereum decentralized applications and smart contracts. ETH is the short ticker symbol for Ethereum, which is often used on exchanges and other financial platforms. Ethereum is a platform for creating and running smart contracts.
Ethereum
  1. Ethereum - An open source, decentralized platform based on blockchain technology created by Vitalik Buterin in 2013. It runs smart contracts on a custom built blockchain that allows developers to create markets, store registries of debts, and so on.
  2. A platform for creating and running smart contracts. These are programmable applications that run exactly as promised - without downtime, censorship, or interference.
  3. Blockchain application that uses a built-in programming language that allows users to build decentralized ledgers modified to their own needs. Smart contracts are used to validate transactions in the ledger.
  4. Ethereum is a blockchain-based decentralized platform for apps that run smart contracts and is aimed at solving issues associated with censorship, fraud and third-party interference.
  5. Ethereum is an open software platform based on blockchain technology that enables developers to write smart contracts and build and deploy decentralized applications.
  6. A blockchain platform created in 2015 by a programmer of Russian origin Vitalik Buterin. It allows you to create decentralized apps based on smart contracts.
  7. Ethereum is an open software platform based on blockchain technology that enables developers to write smart contracts and build and deploy decentralized applications(Dapps). The native token of the blockchain is called Ether which is used to pay for transaction fees, miner rewards and other services on the network. The main innovation of Ethereum is the Ethereum Virtual Machine (EVM) which runs on the Ethereum network and enables anyone to run any application. The EVM makes the process of developing blockchain applications much easier. Before the emergence of Ethereum developers had to develop a dedicated blockchain for each application they wanted to create. This process is time-consuming and resource-intensive. Ethereum will enable the development of many applications on the same platform, making the process much easier and accessible for developers. The Ethereum Project, based in Switzerland, raised millions in seed money by pre-mining and selling ethers to supporters & investors. As opposed to Bitcoin, its scripting language is Turing-complete and full-featured, expanding the kinds of smart contracts that it can support. The Ethereum project wants to “decentralize the web” by introducing four components as part of its roadmap: static content publication, dynamic messages, trustless transactions and an integrated user-interface
  8. A public blockchain system developed as an open-source project, its architecture running remotely on the Ethereum Virtual Machine. It uses ‘ethers’, a cryptocurrency, as its token and supports the storage and execution of ‘smart contracts’.
  9. The blockchain behind the second largest cryptocurrency. Ethereum differentiates itself from Bitcoin by allowing programmers to build on top of the blockchain with a Turing-complete programming language. This allows programmers to build distributed applications. While Bitcoin can be seen as one application (transfer of value) on the distributed web just like email, Ethereum is a network that allows for many different applications to come to the fore. The cryptocurrency associated with the Ethereum blockchain is known as Ether.
Ethereum Classic (ETC)
  1. A type of cryptocurrency that is a continuation of the original Ethereum blockchain following the DAO attack in June 2016. Ethereum is essentially a hard fork of the blockchain that was formed to refund the money that was siphoned during the attack (around $50 million). Ethereum Classic assumes no hard fork occurred and is supported by those who believe in complete immutability of the blockchain.
  2. Ethereum Classic (ETC) is not a new cryptocurrency, but instead a split from an existing cryptocurrency, Ethereum. Both blockchains are identical in every way up until block 1920000 where the hard-fork to refund The DAO token holders was implemented, meaning that all the balances, wallets, and transactions that happened on Ethereum until the hard-fork are still valid on the Ethereum Classic Blockchain. After the hard-fork, the blockchains were split in two and act individually. ETC still offers the same features as Ethereum, such as the creation and deployment of smart contract and Decentralized applications, and has all the same specifications. ETC was essentially created as a way to allow smart contracts to run exactly as they are programmed to, without the interference of a third party. The ETC community argues that the DAO smart contract did what it was programmed to do and that no action should be taken to censor the contract.
EVM // Ethereum Virtual Machine
  1. The Ethereum Virtual Machine (EVM) is a Turing complete virtual machine that allows anyone to execute arbitrary EVM Byte Code. Every Ethereum node runs on the EVM to maintain consensus across the blockchain.
  2. The Ethereum Virtual Machine (EVM) is a simple but powerful, Turing complete 256bit Virtual Machine that allows anyone to execute arbitrary EVM Byte Code. The EVM is part of the Ethereum Protocol and plays a crucial role in the consensus engine of the Ethereum system. It allows anyone to execute arbitrary code in a trust-less environment in which the outcome of an execution can be guaranteed and is fully deterministic. Executing code within the Ethereum network takes time, and execution is generally pretty slow compared to other VMs.
  3. An emulated computer system, or a distributed system that is designed to replicate the features of a computer's architecture.
EVM Code
  1. EVM Code Is the programming language in which accounts on the Ethereum blockchain can contain code. The EVM code associated with an account is executed every time a message is sent to that account and has the ability to read/write storage and send itself messages.
    Reference:
Exchange Traded Fund (ETF)
  1. A security that tracks a basket of assets such as stocks, bonds, and cryptocurrencies but can be traded like a single stock. Bought and sold on traditional stock exchanges.
Exchanges // Exchange // Cryptocurrency Exchange
  1. A marketplace for cryptocurrencies where users can buy and sell coins.
  2. A crypto exchange is a digital marketplace where traders can buy and sell tokens using different fiat currencies or altcoins. A cryptocurrency exchange is an online platform that acts as an intermediary between buyers and sellers of the cryptocurrency. Some popular exchanges in North America are Coinbase, GDAX, Gemini, Polinex, Bittrex, Kraken, Quadriga, etc.
  3. Cryptocurrency exchanges are websites or services that let you exchange digital cryptoassets and cryptocurrencies between one another or exchange fiat currencies such as the US dollar for cryptoassets. Two of the most prominent examples of these exchanges are Coinbase and Binance.
Extinct Blocks
  1. Extinct blocks are valid blocks which are not part of the main chain. They can occur naturally when two miners produce blocks at similar times or they can be caused by an attacker with enough hashing power attempting to reverse transactions.
F
Faucet
  1. Services on the Internet which will give registered users small quantities of bitcoin for completing specific online activities such as ad viewing and form filling. The value of bitcoin given out for free is usually in the fractions of a cent.
  2. If you find a website that offers to give you free cryptocurrency for connecting with them, it is termed a Faucet. The majority of these are scams.
Fiat Currency // Fiat
  1. Government-issued currency, such as the US Dollar or Euro.
  2. Fiat currency is any money declared by a government to be to be valid for meeting a financial obligation, like USD or EUR.
    Reference: MIT
  3. Refers to currencies that have minimal or no intrinsic value themselves (i.e. they are not backed by commodities like gold or silver) but are defined as legal tender by the government, such as paper bills and coins.
  4. Any money declared by a government to be to be valid for meeting a financial obligation, like USD or EUR
  5. A term used to describe traditional government-issued and backed currencies like dollars, Euros, and Yen. Not backed by physical commodities but by legal tender laws.
  6. Money that a government has declared to be legal tender.
Flipping
  1. Flipping is a type of investment strategy (popular in real estate investing) where you buy something with the goal of reselling for a profit later, usually in a short period of time. In the context of crypto-economics, flipping refers to the strategy of investing in tokens before they are listed on the exchanges and reselling them for a profit when they are trading in the secondary market.
  2. A type of investment strategy (popular in real estate investing) where you buy something with the goal of reselling for a profit later, usually in a short period of time. In the context of ICOs, flipping refers to the strategy of investing in tokens before they are listed on the exchanges and reselling them for a profit when they are trading in the secondary market.
  3. A potential future event, hoped for by Ethereum fans, where the total market cap of Ethereum surpasses the total market cap of Bitcoin - making Ethereum the most valuable.
FOMO
  1. Internet culture term that stands for Fear of Missing Out. Describes actions taken by investors based on emotions and the fear of not benefitting from a price rise or drop.
  2. An acronym that stands for 'fear of missing out' and in the context of investing, refers to the feeling of apprehension for missing out on a potentially profitable investment opportunity and regretting it later.
Fork
  1. A fork or accidental fork is a split in the digital recordings, known as the blockchain. A blockchain is the technology for creating permanent, secure digital recordings. Imagine the blockchain as a book of records where each new page in that book is what is known as a “block”. Blocks are attached to each other making what is known as the blockchain. There are hundreds of blockchains created by many groups to record all sorts of information. Each blockchain is maintained simultaneously by a network of computers connected by the Internet. Updates to the blockchain are seen immediately and manipulation is extremely difficult, perhaps impossible. With blockchains, only one recording (block) should be made at a time. However, sometimes two blocks are created at once by two computers, both valid. Because all recordings are shared among the network of computers, one block will reach one group of computers first while the second block will reach the other group of computers. This creates a split in the blockchain record, known as a fork. Eventually, a computer in the network will build another block on one of the forks and it will grow. The computers always identify the longer fork as the correct one, and so will smoothly switch over, abandoning the shorter one.
  2. A change to the way a blockchain’s software rules define valid transactions or blocks. Hard fork: A change to the rules that all nodes on a network must adapt, or else leave the network. Soft fork: A backward-compatible change that hinges only on a majority of nodes’ adopting the new rules.
  3. Forks create an alternate version of the blockchain, leaving two blockchains to run simultaneously on different parts of the network.
    Reference: MIT
  4. When a new version of a blockchain is created, resulting in two versions of the blockchain running side-by-side, it is termed a Fork. As a single blockchain forks into two, they will both run on the same network. Forks are categorised into two categories: soft or hard.
  5. A situation where a blockchain splits into two separate chains, causing the creation of an ongoing alternative version of the blockchain, by creating two blocks simultaneously on different parts of the network. Forks generally happen in the crypto-world when new ‘governance rules’ are built into the blockchain’s code. This creates two parallel blockchains, where one of the two is the winning blockchain. The winning blockchain gets determined by its users, by the majority choosing on which blockchain their clients should be following.
  6. A change to the software and rules of a cryptocurrency that creates two separate versions of the currency's blockchain. Forks can be soft forks or hard forks, see below.
  7. When two or more blocks have the same block height, forking the blockchain. Typically occurs when two or more miners find blocks at nearly the same time. Can also happen as part of an attack. Synonyms: Fork Not To Be Confused With: Hard fork (a change in consensus rules that breaks security for nodes that don’t upgrade) Soft fork (a change in consensus rules that weakens security for nodes that don’t upgrade) Software fork (when one or more developers permanently develops a codebase separately from other developers) Git fork (when one or more developers temporarily develops a codebase separately from other developers)
  8. Is a creation of an alternative successful version of the blockchain. The fork is often called a new cryptocurrency, which is based on the protocol of the existing one. For example, Litecoin (LTC) is a Bitcoin fork (BTC).
  9. The creation of an ongoing alternative version of the blockchain, by creating two blocks simultaneously on different parts of the network. This creates two parallel blockchains, where one of the two is the winning blockchain. The winning blockchain gets determined by its users, by the majority choosing on which blockchain their clients should be listening
  10. Alters the blockchain data in a public blockchain.
  11. Forks create an alternate version of the blockchain, leaving two blockchains to run simultaneously on different parts of the network.
  12. A fork is the creation of an ongoing alternative version of the blockchain, by creating two blocks simultaneously on different parts of the network. This creates two parallel blockchains, where one of the two tends to eventually become the winning blockchain. The winning blockchain gets determined by its users, by the majority choosing on which blockchain their clients should be operating. Forks require a unanimous decision on behalf of the programmers in order to execute the action of a fork.
  13. There are soft forks, where a cryptocurrency maintains its value and its rules are simply rolled forward and changed in a reversible manner, usually with the assent of the majority of the community. Hard forks are when a blockchain fails to reach consensus and has to do a hard reset and splits off into two chains. One chain adopts one set of rules and another continues the original set of rules. This is non-reversible. A hard fork is how Bitcoin and Bitcoin Cash split.
Free Transaction
  1. Transactions that don’t have to pay a transaction fee because their inputs have been idle long enough to accumulated large amounts of priority. Note: miners choose whether to accept free transactions. Synonyms: High-priority transaction || Free transaction
Frontier
  1. Frontier was the initial release of the Ethereum network, which went live in July 2015. The release offered a minimal framework, although it did enable more technologically savvy developers to release their own apps, as well as accounting for mining and development of exchanges. Frontier was successful – no major bugs – so the foundation moved on to the next update, Homestead.
FUD
  1. An acronym that stands for fear, uncertainty and doubt. It is a strategy to influence perception by spreading negative, misleading or false information about something, as opposed to reasoned criticism.
  2. Internet culture term that stands for Fear, Uncertainty, and Doubt. It means negative information that is being purposefully spread about an asset to make people sell.
Full Node
  1. Node that fully enforces all of the rules of the blockchain
  2. A full node is a program that fully validates transactions and blocks. Almost all full nodes also help the network by accepting transactions and blocks from other full nodes, validating those transactions and blocks, and then relaying them to further full nodes. It is also the node that fully enforces all of the rules of the specified blockchain.
  3. A computer that connects to the Bitcoin network. Synonyms: Node || Full node || Archival node || Pruned node || Peer Not To Be Confused With: Lightweight node || SPV node
  4. Full node is defined as a computer in a network that has a complete, current copy of the blockchain ledger, and verifies the correctness of transactions and new blocks. A node is defined as any computing device (computer, phone, etc.) that is maintaining a network. Cryptocurrencies are supported by a network of computers each keeping a digital record of the data known as a blockchain. A computer, a phone, or any other computing device that can receive, transmit, and/or contribute to the blockchain is a node. When talking about blockchain technology, we have two types of full nodes: A full node that maintains an entire copy of the blockchain program and also receives, records, verifies, and transmits transactions on the blockchain. This process is known as “mining”. A full node that only receives and transmits transactions on the blockchain program. This process is passive and relies on a mining full node for updates.
  5. A computer that fully implements the entirety of rules of an underlying blockchain network and completely validates transactions and blocks on a blockchain.
Fundamental Analysis (FA)
  1. Evaluating an asset based on its underlying characteristics and traits as an effort towards arriving at an intrinsic value of the asset.
Fungible
  1. A description of an item, usually money, goods or a commodity, whose individual or divided units, can replace or be replaced by another identical item. In summary, fungible items are mutually interchangeable. Money is considered a good example of fungibility, as a $100 note may be replaced by another $100 note, or may replace two $50 notes or ten $10 notes. A diamond is less fungible as not all diamonds are equal, and variations in their cut, colour and clarity makes it hard to determine if two sets of diamonds are of equal value for a direct exchange or replacement.
Futures
  1. Contracts to buy assets (like cryptocurrencies and stocks) with an agreement for future delivery on a regulated stock exchange. Used to speculate on the future price of an asset.
  2. This is a pre-approved contract between two entities to fulfil a transaction when the value of cryptocurrency hits a certain price. It's different from a Limit Order in that the buyer and seller are already nominated and bound. A future contract becomes relevant when a buyer wants to go Short, and a seller wants to go Long on the asset.
G
Gas
  1. Gas a is measurement given to an operation in the Ethereum network that relates to the computational power required to complete it. That measurement relates to the fee offered to miners who process that transaction. Other operations have a small cost of 3 to 10 gas, but a full transaction costs 21000 gas.
  2. To run decentralized applications and smart contracts on the Ethereum network, apps calculate their usage using an internal pricing unit called Gas. Actual fees are then paid in Ether.
  3. Measures how much work an action takes to perform in Ethereum.
  4. Gas is a measurement roughly equivalent to computational steps (for Ethereum). Every transaction is required to include a gas limit and a fee that it is willing to pay per gas; miners have the choice of including the transaction and collecting the fee or not. Every operation has a gas expenditure; for most operations it is ~3–10, although some expensive operations have expenditures up to 700 and a transaction itself has an expenditure of 21000.
  5. A term used in the Ethereum platform that refers to the maximum number of units of gas the user is willing to spend on a transaction. The transaction must have enough gas to cover the computational resources needed to execute the code. All unused gas is refunded at the end of the transaction.
  6. Gas is used as a transactional cost in the Ethereum blockchain. When you use Ether to access distributed applications, you have to spend a portion of gas associated with it. Gas is correlated with how much computational work your request takes. This ensures that transactional costs are rightly set for the amount of work the system needs to do. Gas is a way to ensure that nobody tries to attack the Ethereum network by filling it with invalid requests.
Gas Limit
  1. A term used in the Ethereum platform that refers to the maximum amount of units of gas the user is willing to spend on a transaction. The transaction must have enough gas to cover the computational resources needed to execute the code. All unused gas is refunded at the end of the transaction.
  2. When a user makes a transaction in the Ethereum network, they set their Gas Limit, which is the most they are willing to pay as a fee for that transaction. If the transaction is going to cost more Gas than what is offered, the transaction will not go through. If it costs less, the difference will be refunded.
Gas Price
  1. A term used in the Ethereum platform that refers to the price you are willing to pay for a transaction. Setting a higher gas price will make miners more incentivized to prioritize and validate that particular transaction ahead of those set with a lower gas price. Gas prices are typically denominated in Gwei.
  2. The amount you are willing to pay for a transaction in the Ethereum network. If you want miners to process your transaction fast, then you should offer a higher price. Gas prices are usually denominated in Gwei.
General Purpose Technology // GPT
  1. A new method of producing and inventing that is important enough to have a protracted aggregate impact across multiple applications and sectors of the economy. Electricity and information technology (IT) probably are the two most important GPTs so far.
    Reference: MIT
Genesis Block
  1. The first or first few blocks of a blockchain. Modern versions of Bitcoin number it as block 0, though very early versions counted it as block 1. The genesis block is almost always hardcoded into the software of the applications that utilize its blockchain.
  2. The very first block in the blockchain.
  3. A blockchain is a string of "blocks" that are linked together in order. Each block is a collection of bundled transactions. The genesis block is the very first block of a blockchain.
  4. The first block in the Bitcoin blockchain. Synonyms: Genesis block || Block 0 Not To Be Confused With: Generation transaction (the first transaction in a block)
  5. The first block of data that is processed and validated to form a new blockchain, often referred to as block 0 or block 1.
Genesis Long
  1. A margin trade that profits if the price increases.
Genesis Short
  1. A margin trade that profits if the price decreases.
Golang (Google language)
  1. Created by google in 2009 golang is a programming language based on c
Gossip Protocol
  1. A gossip protocol is a procedure or process of computer-computer communication that is based on the way social networks disseminate information or how epidemics spread. It is a communication protocol.
H
Halving
  1. Every time miners approve transactions on the Bitcoin blockchain, they earn Bitcoin. As each block on the blockchain fills up with transactions, a certain amount of Bitcoin enter the marketplace. However, the number of Bitcoin that will ever be created is finite; locked at 21 million. In order to ensure this cap is kept, the amount of Bitcoin earned by miners for filling one block is halved at the completion of that block. This is called Halving. For the record, by the year 2140, all 21 million Bitcoin will be in circulation.
  2. Bitcoin's supply of newly generated coins is cut in half about every four years to keep it scarce. This 50% cut if known as the halving. The next halving will happen around 2020.
  3. Bitcoins have a finite supply, which makes them a scarce digital commodity. The total amount of bitcoins that will ever be issued is 21 million. The number of bitcoins generated per block is decreased 50% every four years. This is called “halving.” The Bitcoin block mining reward halves every 210,000 blocks. The final halving will take place in the year 2140.
  4. A reduction in the block reward given to crypto-currency miners once a certain number of blocks have been mined. The Bitcoin block mining reward halves every 210,000 blocks.
  5. When the block reward of a crypto asset, such as bitcoin, drops to one-half of what it was before; this is used to create a decaying rate of issuance to arrive at an eventual finite supply of a crypto asset.
Hard Cap
  1. The maximum amount that an ICO will be raising. If an ICO reaches its hard cap, they will stop collecting any more funds.
Hard Fork // Hardfork
  1. Alters the blockchain data in a public blockchain. Requires all nodes in a network to upgrade and agree on the new version.
  2. A Hard Fork is a change to the blockchain protocol that makes previously invalid blocks/transactions valid, and therefore requires all users to upgrade their clients. The most recent example of a hard fork in public blockchains is the Ethereum hard fork which happened on July 21st, 2016. The hard fork changed the Ethereum protocol, therefore a second blockchain emerged (Ethereum Classic, ETC) which supports the old Ethereum protocol. In order to continue existing ETC needs miners, which would validate the transactions on the blockchain.
  3. A type of fork that renders previously invalid transactions valid, and vice versa. This type of fork requires all nodes and users to upgrade to the latest version of the protocol software.
  4. A permanent divergence in the blockchain, commonly occurs when non-upgraded nodes can’t validate blocks created by upgraded nodes that follow newer consensus rules. Synonyms: Hard fork Not To Be Confused With: Fork (a regular fork where all nodes follow the same consensus rules, so the fork is resolved once one chain has more proof of work than another) Soft fork (a temporary divergence in the blockchain caused by non-upgraded nodes not following new consensus rules) Software fork (when one or more developers permanently develops a codebase separately from other developers)
  5. A change to the rules of a cryptocurrency that creates two separate versions of the blockchain. Hard forks are changes that are not backward compatible with previous rules.
  6. Hard fork is defined as a decision to make a permanent change to the technology used by a cryptocurrency. This change makes all new recordings (blocks) very different from the original blocks. They are changed so much that new blocks are seen as invalid to anyone who didn’t upgrade their technology. Which means, any computer that is not updated with the new technology, will find these new blocks appear invalid. This process can cause a lot of trouble which is why, for a hard fork to go smoothly, it is important everyone agrees to the change. Any new fork in the blockchain can fail and if it does, all users will return to the original recording.
Hardware Wallet
  1. A physical storage device for cryptocurrencies that uses special technologies to protect the assets on it. Examples of hardware wallets are the products Ledger Nano S and Trezor.
  2. A device that can securely store crypto-currency. Hardware wallets are often regarded as the most secure way to hold crypto-currency. Usually in the format of some sort of USB drive.
Hash
  1. The act of performing a hash function on the output data. This is used for confirming coin transactions.
  2. The result of applying an algorithmic function to data in order to convert them into a random string of numbers and letters. This acts as a digital fingerprint of that data, allowing it to be locked in place within the blockchain
  3. A hash function is any function that can be used to map data of arbitrary size to data of fixed size. The values returned by a hash function are called hash values, hash codes, digests, or simply hashes. One use is a data structure called a hash table, widely used in computer software for rapid data lookup. This is used for confirming coin transactions by miners on the blockchain network.
  4. A hash is the result of a function that transforms data into a unique, fixed-length digest that cannot be reversed to produce the input. It can be viewed as the digital version of a fingerprint, for any type of data.
Hash Functions //Hash function
  1. Cryptographic computer code works like a one-way street. It's easy to decipher 250 + 250 = ? but much harder to find the correct answer (out of many) for ? + ? = 500.
  2. A cryptographic function that turns any input into a string of characters of a fixed length that serves as a virtually unforgeable digital fingerprint of the data, called a hash.
    Reference: MIT
  3. A cryptographic hash function is a mathematical algorithm that takes a particular input which can be any kind of digital data be it a password or jpeg file and produces a single fixed length output. Some examples of different hash function algorithms are MD5, MD4 or SHA256. The last one is used in the Bitcoin protocol. Main properties: (1) easy to compute hash value for any given message (2) infeasible to generate a message from its hash except by trying all possible input combinations(brute force attack) (3) infeasible to modify a message without changing the hash (4) infeasible to find two different messages with the same hash (5) deterministic so the same message always results in the same hash. Cryptographic hash functions have many information security applications, notably in digital signatures, message authentication codes (MACs), and other forms of authentication. They can also be used as ordinary hash functions, to index data in hash tables, for fingerprinting, to detect duplicate data or uniquely identify files, and as checksums to detect accidental data corruption.
  4. A function that maps data of an arbitrary size
  5. A cryptography tool that turns any input into a string of characters that serves as a virtually unforgeable digital fingerprint of the data, called a hash.
  6. A more technical and precise description of the underlying technical foundation of how data is shared and stored on a blockchain. Hash tables are a mainstay of computer science.
Hash Rate
  1. The hash rate is the measuring unit of the processing power of the Bitcoin network. The Bitcoin network must make intensive mathematical operations for security purposes. When the network reached a hash rate of 10 Th/s, it meant it could make 10 trillion calculations per second.
  2. Hash Rate is the measurement of performance for the mining rig is expressed in hashes per second. Hash rates represent the number of hashes that can be performed by a bitcoin miner in a given period of time (usually takes about a second).
  3. Measurement of performance for the mining rig is expressed in hashes per second.
  4. Is the number of hashes that can be performed by a bitcoin miner in a given period of time (usually a second).
  5. The number of hash computations that can be performed by a cryptocurrency miner with their computer hardware. The rate determines their mining effectiveness and profit.
  6. A measure of the computing power dedicated to any blockchain by the miners validating transactions and blocks. The higher the hash rate, the more active the chain is and the more appealing it is to miners. It then becomes harder to attack the chain, and infiltrate it with false transactions (known as a 51% attack).
Hashcash
  1. Hash Cash is a proof-of-work system used to limit email spam and denial-of-service attacks and more recently has become known for its use in bitcoin (and other cryptocurrencies) as part of the mining algorithm. Hashcash was proposed in May 1997 by Adam Back.
HashGraph
  1. HashGraph is a directed acyclic graph which has the properties of distributed ledger technology. It is different from blockchain. Also, it solves many problems that the blockchain has. For example, it is more secure, faster and fair to its users. It can easily be termed as “new generation blockchain.”
  2. Hashgraph is a new consensus alternative to the blockchain. It uses a gossip protocol that works in the following manner: Every node in Hashgraph can spread signed information (called events) on newly-created transactions and transactions received from others to its randomly chosen neighbors
Header Chain
  1. A chain of block headers with each header linking to the header that preceded it; the most-difficult-to-recreate chain is the best header chain Synonyms: Header chain || Best header chain Not To Be Confused With: Block chain
Headers-First
  1. Synchronizing the block chain by downloading block headers before downloading the full blocks. Synonyms: Headers-first sync Not To Be Confused With: Blocks-first sync (Downloading entire blocks immediately without first getting their headers
Height
  1. The number of blocks preceding a particular block on a blockchain. For example, the genesis block has a height of zero because zero block preceded it. Synonyms: Height || Block height
Hierarchical Deterministic (HD) protocol
  1. The Hierarchical Deterministic (HD) key creation and transfer protocol (BIP32), which allows creating child keys from parent keys in a hierarchy. Wallets using the HD protocol are called HD wallets. Synonyms: HD protocol || HD wallet
High-Priority Transaction
  1. Transactions that don’t have to pay a transaction fee because their inputs have been idle long enough to accumulated large amounts of priority. Note: miners choose whether to accept free transactions. Synonyms: High-priority transaction || Free transaction
HODL
  1. A type of passive investment strategy where you hold an investment for a long period of time, regardless of market volatility. The term was made famous by a typo made in a bitcoin forum. Also referred to as 'buy and hold' or 'hold on for dear life'.
  2. Internet culture term that stands for the resolve to hold assets over a longer period without selling. Became popular after an internet user misspelled the word hold.
  3. A type of passive investment strategy where you hold an investment for a long period of time, regardless of market volatility. The term was made famous by a typo made in a bitcoin forum.
  4. A typo of "Hold" originating from bitcointalk.org that has also been retrofitted to be an acronym for Hold on for Dear Life - to maintain ownership of coins and not sell.
Homestead
  1. Homestead was planned to be released after a month of frontier going live as a best case scenario. As of January 2016 the Homestead release was about 80% complete – but the goals have been altered somewhat as frontier took in a large part of its projected development pipeline – for example the block reward was set to the full 5 ether. In its new form, Homestead has become more of a patchwork of fixes to remove the risk warning attached to the ethereum homepage. Homestead made the second release on March 15, 2016, following Frontier, which is a beta version. Frontier that was affected by unstable operations, but Homestead is stable thanks to a distributed network In addition, due to the shift to Homestead, it became easy to enter the application development on Ethernet, and it became more attractive from financial institutions and major companies, including the use of SDK in the block chain environment by Microsoft.
Honeypot
  1. A mechanism used in computer security used to detect or counteract unauthorized access of information systems.
Hot Storage
  1. The online safekeeping of private keys which allow for access to cryptocurrency funds. Typically this is done through open-source online wallets and digital asset exchanges.
Hybrid PoS/PoW
  1. A hybrid PoS/PoW allows for both Proof of Stake and Proof of Work as consensus distribution algorithms on the network. In this method, a balance between miners and voters (holders) may be achieved, creating a system of community-based governance by both insiders (holders) and outsiders (miners).
Hyperledger
  1. Started by the Linux Foundation, Hyperledger is an umbrella project of open source blockchains
  2. An umbrella project set up by the Linux Foundation comprising various tools and systems for building open-source blockchains.
  3. Hyperledger is an umbrella project of open source blockchains and related tools, started in December 2015 by the Linux Foundation, to support the collaborative development of blockchain-based distributed ledgers.
Hyperledger Composer
  1. Hyperledger Composer is Blockchain Application Development framework which simplify the blockchain application development on Hyperledger Fabric
Hyperledger Fabric
  1. Hyperledger project hosted by Linux which hosts smart contracts called chain code.
Hyperledger Iroha
  1. It is a modular distributed ledger platform emphasis on mobile application development.
    Reference: BTA
Hyperledger Sawtooth Lake
  1. It is a modular Blockchain suite where the transaction business logic is delinked from the consensus layer.
    Reference: BTA
I
Iceberg Order
  1. A conditional order to buy or sell a large amount of assets in smaller predetermined quantities in order to conceal the total order quantity.
Immutable
  1. “unable to be changed” Data stored in a blockchain is unable to be changed.(not even by administrators)
Initial Block Download (IBD)
  1. The process used by a new node (or long-offline node) to download a large number of blocks to catch up to the tip of the best block chain.
Initial Coin Offering // ICO // Initial Token Offering
  1. A blockchain-based fund-raising mechanism in which entrepreneurs mint new crypto-tokens and sell them to investors.
  2. A fundraising method in which new projects will sell their cryptocurrency to investors.
  3. Is an event in which a new cryptocurrency sells advance tokens from its overall coinbase, in exchange for upfront capital. ICOs are frequently used for developers of a new cryptocurrency to raise capital.
  4. An unregulated means by which a cryptocurrency venture, typically early stage, can raise money from supporters by issuing tokens. It is often referred to as a crowdsale as ICO participants may potentially earn a return on their investments (as opposed to crowdfunding, where supporters donate money to a project or cause). Ethereum is currently the most popular platform for launching ICOs.
  5. An Initial Coin Offering is somewhat similar to an IPO in the non-crypto world. Startups issue their own token in exchange for ether or bitcoin. This is essentially crowdfunding in exchange for a token.
  6. A public, crowdfunded sale of cryptocurrency tokens to raise money for a project. Typically, company-specific tokens are offered in exchange for Bitcoin and Ethereum.
  7. The form in which capital is raised to fund new cryptocurrency ventures. Modeled after an Initial public offering (IPO). Funders of an ICO receive tokens.
  8. ICOs are types of crowdfunding mechanisms conducted on the blockchain. An ICO is an event in which a new cryptocurrency sells advance tokens from its overall coinbase, in exchange for upfront capital. ICOs are frequently used for developers of a new cryptocurrency to raise capital. The way it works is entrepreneurs present a whitepaper describing the business model and the technical specifications of a project before the ICO. They lay out a timeline for the project and set a target budget where they describe the future funds spending (marketing, R&D, etc.) as well as coin distribution (how many coins are they going to keep for themselves, token supply, etc.). During the crowdfunding campaign, investors purchase tokens with already established cryptocurrencies like Bitcoin and Ethereum.
  9. A blockchain-based fundraising mechanism in which entrepreneurs mint new crypto tokens and sell them to investors.
    Reference: MIT
  10. Another way to originate tokens for a blockchain. An ICO involves a marketing process, private sale, then a public sale of a newly-listed token, which then aims to be listed on as many cryptocurrency exchanges as possible. Note that there is no standard way of conducting initial coin offerings.
Initial Exchange Offering (IEO)
  1. Where a project first lists and offers its tokens on an exchange instead of an Initial Coin Offering.
Initial Token Offering (ITO)
  1. Generally, the terms ICO and ITO are used interchangeably. However, the first generation of digital assets were called coins like Bitcoin or Litecoin. Coins have been used as a digital medium of doing transactions in an elegant encrypted way. The next generation of digital assets are called tokens, which cover a broader purpose of use.
Interoperability
  1. A concept of allowing blockchains to be compatible with each other and build upon each other's features and use-cases. (Examples, Wanchain, Atomic Swaps, and Komodo's Oracles).
  2. Blockchains and cryptocurrencies are often isolated with one another, and need to be exchanged in order to be used. Blockchains like Aion are looking to solve the interoperability piece by making different blockchains and cryptocurrencies interoperable, or compatible with one another: imagine, for example, a world where you can trade Bitcoin and Ethereum seamlessly (without exchanges) and use them interchangeably.
IOTA (MIOTA)
  1. Refers to the cryptocurrency and the name of an open source distributed ledger founded in 2015 that does not use blockchain (it uses a new distributed ledger called the Tangle). It offers features such as zero fees, scalability, fast and secure transactions, and so on. It is focused on the Internet of Things.
IPFS - Inter Planetary File System
  1. The InterPlanetary File System (IPFS) is a hypermedia distribution protocol, addressed by content and identities. IPFS enables the creation of completely distributed applications. It aims to make the web faster, safer, and more open. IPFS is an open source project developed by the team at Interplanetary Networks and many contributors from the open source community. It is a peer-to-peer distributed file system that seeks to connect all computing devices with the same system of files. In some ways, IPFS is similar to the Web, but IPFS could be seen as a single BitTorrent swarm, exchanging objects within one Git repository. In other words, IPFS provides a high throughput content-addressed block storage model, with content-addressed hyperlinks. This forms a generalized Merkle DAG, a data structure upon which one can build versioned file systems, blockchains, and even a Permanent Web. IPFS combines a distributed hash table, an incentivized block exchange, and a self-certifying namespace. IPFS has no single point of failure, and nodes do not need to trust each other.
J
K
Keccak-256
  1. A type of cryptographic hashing function. Ethereum uses Keccak-256.
Know Your Customer (KYC)
  1. Laws and regulations that require banks and other financial institutions to keep and report many details of their customers' personal information and transactions.
  2. KYC is the process of a business identifying and verifying the identity of its clients. The term is also used to refer to the bank and anti-money laundering regulations which governs these activities. Almost all exchanges nowadays are expected to have this protocol implemented.
  3. A standard procedure in the finance industry which allows companies to identify their customers and comply with KYC AML laws. Used to de-risk potential investors. Usually involves taking pictures of government-issued IDs and submitting to a verification service.
L
Lambo
  1. Short for Lamborghini, the luxury sportscar. Popular internet meme that is used to show the large gains made by cryptocurrency investors, who dream of buying the car.
Last Mile Problem
  1. A phrase used to describe the interface between online records and the entities or users they represent in the offline world
    Reference: MIT
Ledger
  1. A ledger is a database where every transaction of a cryptocurrency is recorded. For example, Blockchain is the ledger for Bitcoin transactions. It is a global ledger where every transaction of bitcoin that has ever happened is recorded.
  2. A store of records that can only be appended (added to). It is immutable (unchangeable after the fact). Blockchains use decentralized ledgers as their core technology.
  3. Is an append-only record store, where records are immutable and may hold more general information than financial records.
Light Client
  1. A protocol that allow users in low capacity environments (smart phones, browser extensions, notebooks and tablets) to interact with blockchain.
Light Node
  1. A computer on a blockchain network that only verifies a limited number of transactions relevant to its dealings, making use of the simplified payment verification (SPV) mode.
Lightning Network
  1. The Lightning network is a decentralized network using smart contract functionality on the blockchain to enable instant payments across a network of participants. The Lightning Network will allow bitcoin transactions to happen instantly, without worrying about block confirmation times. It will allow millions of transactions in a few seconds, at low costs, even between different blockchains, as long as both chains use the same cryptographic hash function. The Lightning network will allow two participants on the network to create a ledger entry, conduct a number of transactions between themselves and after the process has finished, record the state of the transactions on the blockchain. As for now, the bitcoin network is capable of processing up to 7 transactions per second. The Visa payment network, for instance, is believed to complete 45,000 transactions per second during a regular holiday period. This protocol tries to solve the bitcoin scalability problem.
  2. A proposed change to Bitcoin's blockchain that's designed to facilitate faster transactions and better scaling. Involves bi-directional payment channels and other changes.
  3. A low latency, off chain P2P system for making micropayments of cryptocurrencies. It offers features such as instant payments, scalability, low cost and cross-chain functionality. Participants do not have to make individual transactions public on the blockchain and security is enforced by smart contracts.
  4. A second layer operating on top of a blockchain, enabling increased transaction speed among participating nodes. This is one proposed scaling solution for Bitcoin. Raiden network is the Ethereum equivalent.
  5. Lightning Network is a proposed implementation of bi-directional payment channels which allows payments to be securely routed across multiple peer-to-peer payment channels. This allows the formation of a network where any peer on the network can pay any other peer even if they do not directly have a channel open between each other. Key features of the Lightning Network are: rapid payments, no third party trust required, multi-signature capable, securely cross blockchains including sidechains and altcoins’, and sub-satoshi payments. The Lightning Network was proposed to help resolve scalability problems associated with the increasing number of transactions that the Bitcoin network has to cope with. The white paper on Lightning Nerwork was put forward by developers Joseph Ppn and Tadge Dryja in 2015 as a way to expand Bitcoin to accommodate millions of transactions per second by building a top-layer to Bitcoin that doesn’t require any additional trust in intermediaries. See also, Segregated Witness.
  6. Lightning Network is an off-chain solution that can settle transactions without having to use the underlying blockchain. It opens up bidirectional payment channels between different individuals, allowing Bitcoin to process many more transactions per second. Payment channels have pre-deposited amounts of crypto placed into them. They allow individuals with channels open between them to transact seamlessly without using the blockchain. Once you get a final balance, it is validated into the blockchain. This allows for many more payments to be done per second. It also means there is some centralization between large payers.
Lightweight client
  1. A method for verifying if particular transactions are included in a block without downloading the entire block. The method is used by some lightweight Bitcoin clients. Synonyms: SPV || Simplified Payment Verification || Lightweight client || Thin client
Limit order // Limit Buy // Limit Sell
  1. Orders placed by traders within a given crypto-exchange to buy or sell a cryptocurrency when the price meets a certain amount. They can be thought of as ‘for-sale’ signs. These orders are what are bought and sold against when traders place market orders.
Litecoin (LTC)
  1. A type of cryptocurrency that was created by former Google employee Charlie Lee in 2011. It offers features such as Segregated Witness and the Lightning Network which allows for faster processing at a lower cost.
  2. An offshoot of Bitcoin with very similar features. However, this cryptocurrency is designed for very cheap and fast transaction. Has the goal to become digital money. LTC is the short ticker symbol for Litecoin, which is often used on exchanges and other financial platforms. Litecoin is an offshoot of Bitcoin with a focus on cheap transactions.
  3. Is a cryptocurrency created in October 2011 by Charles Lee, a former Google engineer. It has an advantage of an approximately 4 times higher processing speed of transactions compared to Bitcoin.
  4. Launched in the year 2011, Litecoin is an alternative cryptocurrency based on the model of Bitcoin. Charlie Lee, a MIT graduate and former Google engineer, is Litecoin's creator. Litecoin is based on an open source global payment network that is not controlled by any central authority. Sometimes referred to as the silver of bitcoin’s gold.
  5. Is a peer-to-peer cryptocurrency based on the Scrypt proof-of-work network. Sometimes referred to as the silver of bitcoin’s gold.
Locktime
  1. Part of a transaction which indicates the earliest time or earliest block when that transaction may be added to the block chain.
Locktime // nLockTime
  1. Part of a transaction which indicates the earliest time or earliest block when that transaction may be added to the blockchain.
M
MACD
  1. MACD stands for “Moving Average Convergence Divergence”. A trend indicator that shows the relationship between two moving averages of prices. MACD indicators can be interpreted using three different methods: Crossovers Divergence Dramatic Rise
Mainnet
  1. The original and main network for Bitcoin transactions, where satoshis have real economic value. Synonyms: Mainnet Not To Be Confused With: - Testnet (an open network very similar to mainnet where satoshis have no value) - Regtest (a private testing node similar to testnet)
Maker (Market Maker)
  1. You become a “maker” when you place an order and it does not trade immediately, so your order stays in the order book and waits for someone else to fill/match with it later.
Margin Trading // Buying on Margin
  1. The act of ‘magnifying’ the intensity of your trades by risking your existing coins. Margin trading is possible due to the existence of the lending market. Lenders provide loans to traders so they can invest in larger amounts of coins, and lenders benefit from interest on the loans. (NOTE: Very risky)
  2. This is some Refers to the trading practice where existing assets are used as collateral for short-term loans. The loans are then used in risky trades to magnify the gain or loss of the trade.text inside of a div block.
  3. Trading using borrowed funds - note: this is a high risk strategy and should only be done by experienced investors. Interest rates apply.
Market Cap
  1. The total value held in a cryptocurrency. It is calculated by multiplying the total supply of coins by the current price of an individual unit.
  2. The total value of an asset, calculated by multiplying the total number of outstanding shares (or coins) and the price per share (or coin). Represents total size and popularity.
  3. The total value held in a cryptocurrency. Market Capitalization is one way to rank the relative size of a cryptocurrency. It is calculated by multiplying the total supply of coins by the current price of an individual unit (or coin).
Market Capitalization
  1. The total trading value of a given coin - calculated by the product of the supply of the coin by the current price.
Market Order // Market Buy // Market Sell
  1. A simple purchase or sale on an exchange at the current price. Market buys purchase the cheapest ETH (or coin) available on the order book, and market sells fill the most expensive buy order on the books.
  2. When a taker picks the best available bid or ask for a cryptocurrency, taking the price and quantity available on the order book.
Masternode
  1. Masternodes are nodes with increased capabilities that enable specialized services (such as instantsends and privatesends on the Dash network). To compensate for the increased cost and upfront investment for hosting a masternode, masternodes are often paid out a percentage of block rewards.
Maximum Supply
Membership Service Provider (MSP)
  1. A Hyperledger Fabric blockchain network can be governed by one or more MSPs
Mempool
  1. A temporary pool where all transaction not yet verified are located and picked up by mining nodes or nodes that create blocks.
Merkle Root
  1. The root node of a Merkle tree, a descendant of all the hashed pairs in the tree. Block headers must include a valid Merkle root descended from all transactions in that block. Not To Be Confused With" Merkle tree (the tree of which the Merkle root is the root node) Merkle block (a partial Merkle branch connecting the root to one or more leaves transactions)
  2. Every transaction has a hash associated with it. In a block, all of the transaction hashes in the block are themselves hashed (sometimes several times — the exact process is complex), and the result is the Merkle root. In other words, the Merkle root is the hash of all the hashes of all the transactions in the block. The Merkle root is a part of the block header. With this scheme, it is possible to securely verify that a transaction has been accepted by the network (and get the number of confirmations) by downloading just the small block headers and Merkle tree – downloading the entire block chain is unnecessary. This feature is currently not used in Bitcoin, but it will be in the future. The idea (as I understand it) is that the Merkle tree allows for you to verify transactions as needed and not include the body of every transaction in the block header, while still providing a way to test the entire blockchain (and therefore proof of work) on every transaction. To understand this, first, understand the concept of a tree. Consider an eight trade block. Imagine each of those eight transactions at the base of a pyramid: these are leaves. Put four “branches” on the second tier of the pyramid and draw two lines from each of them to the leaves so that each branch has two blades attached to it.
Merkle Tree (or Hash tree)
  1. A system that splits complicated hashcode functions into smaller chunks (creating a tree-like shape). This allows for faster verification on large-scale blockchains.
  2. A tree constructed by hashing paired data (the leaves), then pairing and hashing the results until a single hash remains the Merkle root. In Bitcoin, the leaves are almost always transactions from a single block.
  3. The basic idea behind Merkle tree is to have some piece of data that is linking to another. You can do this by linking things together with a cryptographic hash. The content itself can be used to determine the hash. By using the cryptographic hashing we can address the content, and content gets immutable because if you change anything in the data, the cryptographic hash changes and the link will be different. Bitcoin uses cryptographic hashing, where every block points to the previous one. If you modify the block, the hash will change and will make the block invalid. Hash trees are a generalization of hash lists and hash chains.
  4. When it comes to storing data efficiently and securely, Merkle trees certainly have their role to play. A hash tree is the alternative name of a Merkle tree. It is often meant for verifying any data stored and transmitted in and between different computers on a network. The technology has become an integral part of peer-to-peer protocols as of late, including in the cryptocurrency sector. To be more precise, a Merkle tree is designed to ensure blocks of data can receive from other peers in a peer to peer network. More specifically, this information needs to be in its original state, without alterations or corrupted information.In most cases, a Merkle tree comprises of two child nodes under each node on the network. This binary approach reinstated, although it still leaves a lot of room for future improvements. In fact, there does not appear to be a limit as to how many child nodes can be used per node to establish a more secure Merkle tree.
Metropolis
  1. The Metropolis phase will be reached as soon as an official interface is released for technically inexperienced users. Similarly, Mist is to be introduced and its own dapp store. This is expected to include some fully functional programs designed to demonstrate the strength of the Ethereum network. Between the Homestead and the Metropolis release, there will probably be one or more intermediate steps. Metropolis will be implemented in two steps: ・Byzantium ・Constantinople The benefits of the Metropolis update are: -Easier to implement Smart Contract -Enhancement of privacy protection -Enhanced security -Adjustment of Difficulty Bomb
Microtransaction
  1. A business model where very small payments can be made in exchange for digital goods and services. For example, paying a tiny fee for every page of an ebook you read.
Middleman
  1. For cryptocurrencies, a middleman is a traditional intermediary like a bank. It's a central third party that no longer is required in a decentralized Blockchain system.
Miner
  1. An important participant in the blockchain network, who bundles transactions and gets paid in new coins and transaction fees in return for helping to run the system.
  2. A miner is responsible for securing a blockchain based on Proof of Work. Miners use computing power, also known as hash power, to solve mathematical problems. The result of this process is the addition of new blocks to a blockchain.
    Reference: MIT
Miner Activated Soft Fork (MASF)
  1. A Soft Fork activated by through miner signaling. Synonyms: Miner-activated soft fork || MASF Not To Be Confused With User-Activated Soft Fork (a soft fork activated by flag day or node enforcement instead of miner signaling.) Fork (a regular fork where all nodes follow the same consensus rules, so the fork is resolved once one chain has more proof of work than another) Hard fork (a permanent divergence in the blockchain caused by non-upgraded nodes not following new consensus rules) Soft fork (a temporary divergence in the blockchain caused by non-upgraded nodes not following new consensus rules) Software fork (when one or more developers permanently develops a codebase separately from other developers)
Miner Fee
  1. The amount remaining when the value of all outputs in a transaction are subtracted from all inputs in a transaction; the fee is paid to the miner who includes that transaction in a block. Synonyms: Transaction fee || Miners fee Not To Be Confused With: Minimum relay fee (the lowest fee a transaction must pay to be accepted into the memory pool and relayed by Bitcoin Core nodes)
Mining
  1. A practice in proof-of-work systems where computers are dedicated to solving math problems in order to claim the right to mine a block of data and to get an amount of cryptocurrency. How it works in some more detail: the cryptographic mining piece involves solving cryptographic puzzles. A computer needs to find a nonce to combine with unverified transactions to output a verified string.
  2. The process by which nodes in Bitcoin, Ethereum, and many other blockchain systems (those that use the consensus protocol known as proof of work) add new blocks to their respective chains and generate new crypto-tokens.
  3. The process of trying to ‘solve’ the next block. Through mining, the users secure the network and verify computation and transactions. Currently, systems including Bitcoin’s blockchain, miners are incentivized to validate transactions based of off Proof-of-Work (PoW) protocol, fees, and protocol subsidies. PoW typically requires huge amounts of computer processing power. Proof-of-Stake (PoS) is the upcoming, virtualized system of incentivization for validating transactions. Both of these systems provide economic guarantees and a form of consensus by bet. But, Proof-of-Stake relies more heavily on the betting concept. (See our Intermediate Glossary for more specific definitions of PoW and PoS.)
  4. The process of new blocks creation and processing transactions in the blockchain network. For this, the miner receives a reward in the form of tokens or coins of cryptocurrency.
  5. Mining is the act of validating blockchain transactions and competing for a solution to a mathematical puzzle to append a new block in the blockchain. The necessity of validation warrants an incentive for the miners, usually in the form of coins.
    Reference: MIT
  6. The verification of transactions on a blockchain network, in which transactions are added as entries into the blockchain ledger.
  7. Bitcoin mining is the process of making computer hardware do mathematical calculations for the Bitcoin network to confirm transactions and increase security. As a reward for their services, Bitcoin miners can collect transaction fees for the transactions they confirm, along with newly created bitcoins. Mining is a specialized and competitive market where the rewards are divided up according to how much calculation is done. Not all Bitcoin users do Bitcoin mining, and it is not an easy way to make money.
  8. Is the process by which transactions are verified and added to a blockchain. This process of solving cryptographic problems using computing hardware also triggers the release of cryptocurrencies.
  9. The process by which transactions get verified, bundled, and added to the Blockchain. It's an essential part of any cryptocurrency, because it processes all transactions.
  10. Is the act of validating blockchain transactions. The necessity of validation warrants an incentive for the miners, usually in the form of coins. In this cryptocurrency boom, mining can be a lucrative business when done properly. By choosing the most efficient and suitable hardware and mining target, mining can produce a stable form of passive income.
  11. Mining is the act of creating valid Bitcoin blocks, which requires demonstrating proof of work, and miners are devices that mine or people who own those devices. Synonyms: Mining || Miner
  12. A process where transactions are verified and added to a blockchain. It is also the process where new bitcoins or certain altcoins are created. In theory, anyone with the necessary hardware and access to the internet can be a miner and earn income, but the cost of industrial hardware and electricity has limited mining for bitcoins and certain altcoins today to large-scale operations.
  13. Mining is the process of adding transaction records to Bitcoin’s public ledger of past transactions or blockchain. This ledger of past transactions is called the blockchain as it is a chain of blocks. The blockchain serves to confirm transactions to the rest of the network as having taken place. Bitcoin nodes use the blockchain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere. Mining is intentionally designed to be resource-intensive and challenging so that the number of blocks found each day by miners remains steady. Individual blocks must contain a proof of work to be considered valid. This proof of work is verified by other Bitcoin nodes each time they receive a block. Bitcoin uses the hashcash proof-of-work function. The primary purpose of mining is to allow Bitcoin nodes to reach a secure, tamper-resistant consensus. Mining is also the mechanism used to introduce Bitcoins into the system: Miners are paid any transaction fees as well as a “subsidy” of newly created coins. This both serves the purpose of disseminating new coins in a decentralized manner as well as motivating people to provide security for the system.
  14. The act of validating Blockchain transactions. Requires computing power and electricity to solve “puzzles”. Mining rewards coins based on your computing power.
  15. Mining is the process by which transactions are verified and added to a blockchain. This process of solving cryptographic problems using computing hardware also triggers the release of cryptocurrencies within a given blockchain.
Mining Farm
  1. A collection of many miners, often in a warehouse or large data center devoted to mining cryptocurrencies
Mining Pool
  1. Mining pools are a way for miners to make sure that they get paid on a more frequent basis. Even if someone has a large amount of hashing power to point at the Bitcoin network, it doesn’t necessarily mean that they are going to get a block reward on a regular basis. For example, someone with 10% of the network hashrate is expected to receive 10% of the block rewards. This means that the miner is going to receive nothing 90% of the time. If that miner joins a mining pool that collectively has 40% of the network hashrate, then he or she will receive a payment on 40% of Bitcoin blocks. A mining pool is basically a way for miners to pull their resources together to ensure more frequent payments, even though their share of those payments will be lower.
  2. A group of people or organizations who come together to pool and share their computer resources for cryptocurrency mining. They then also split the rewards.
  3. In a mining pool, different users organize together in order to provide computing power for the bitcoin network. If a Bitcoin block is newly created, each of the users in the mining pool receives its fair share proportionately to his mining power. To become a member of a mining pool, the user needs to run software provided by the mining pool. The advantage of the mining pools is that block rewards get distributed across the pool providing more stable income.
  4. If a number of miners combine their computing power together to try and help complete the transactions required to start a new block in the blockchain, they are in a Mining Pool. The rewards are spread between those in the Mining Pool proportionately based on the amount of power they contributed. The idea is that being in a Mining Pool allows for more chance of successful hashing, and therefore getting enough cryptocurrency reward to have an income.
  5. Multiple users that combine their computing power to mine on the blockchain. Newly created blocks are proportionally shared with users according to mining power. The mining pool itself provides the software necessary to mine, and gives the advantage of rewards getting distributed across the pool, providing stable income.
  6. A mining pool aggregates computing resources dedicated to mining cryptocurrencies and allocates any of the mined blocks proportionally. In practice, mining cryptocurrencies has some randomness to it, so mining pools serve an essential purpose in keeping volatility down for individual miners.
Mining Reward
  1. The payment resulting from volunteering computer resources to process cryptocurrency transactions. Mining rewards are often a mix of new coins and transaction fees.
Mining Rig // Mining Hardware
  1. A computer setup that's specially designed for mining a cryptocurrency. Often involves multiple graphic cards (GPUs) or other complicated setups for maximum efficiency.
  2. A collection of miners who come together to share their processing power over a network and agree to split the rewards of a new block found within the pool.
  3. A computer specially designed for processing proof-of-work blockchains, like Ethereum. They often consist of multiple high-end graphics processors (GPUs) to maximize their processing power.
  4. Although it was rather easy to mine bitcoins in the early days of the network, the increased value of bitcoins has led to people finding more efficient ways to solve the mathematical equations involved with Bitcoin mining. Simple laptops could be used to mine bitcoins back in 2010, but the Bitcoin mining industry has evolved to the point where people now use chips that were created specifically for the purposes of solve blocks and receiving block rewards. This concentration of mining power in more expensive forms of hardware has led to a bit more centralization than what was found in the original creation of the Bitcoin protocol. Many people are priced out of the market due to the expensive nature of ASIC hardware devices.
Mist
  1. Browser for installing and using Dapps
Monero (XMR)
  1. A secure, private, and untraceable cryptocurrency. Monero is focused on being anonymous internet money, hiding your accounts and transactions from anybody but you.
  2. A type of cryptocurrency created in 2014 that is focused on privacy and scalability, and runs on platforms like Windows, Mac, Linux and Android. Transactions on Monero are designed to be untraceable to any particular user or real world identity.
  3. XMR is the short ticker symbol for Monero, which is often used on exchanges and other financial platforms. Monero is a privacy-focused, untraceable cryptocurrency.
Moon // Mooning
  1. Refers to a cryptocurrencies price shooting up to astronomical levels. A popular internet slang term used to describes the positive past or future performance of an asset.
Mt.Gox
  1. Mt. Gox was a Bitcoin exchange based in Shibuya, Tokyo, Japan. Launched in July 2010, by 2013 and into 2014 it was handling over 70% of all Bitcoin transactions worldwide, as the largest Bitcoin intermediary and the world’s leading Bitcoin exchange. In February 2014, Mt. Gox suspended trading, closed its website and exchange service, and filed for bankruptcy protection from creditors.
  2. A bitcoin exchange based in Tokto, Japan which was launched in July 2010 and was handling over 70% of all bitcoin transactions around the world by 2013. In 2014, Mt. Gox announced that about 850,000 bitcoin belonging to the company (circa 100,000 bitcoin) and its customers (744,408 bitcoin) were missing and probably stolen – an amount to the total of approximately US$470 million at that time. Investigations later on indicated that most or all the missing bitcoin were stolen straight out of the Mt. Gox hot wallet over time beginning in late 2011. 200,000 bitcoin were later recovered in an old digital wallet from 2011, but the damage had been done. On 28 February 2014, Mt. Gox filed for bankruptcy protection in Tokyo, and in the US on 9 March 2014 to temporarily halt legal action by traders who alleged the operation was a fraud. On 16 April 2014, Mt. Gox relinquished its plan to rebuild under bankruptcy protection, and asked a Tokyo court to allow it to be liquidated. The domain name mtgox.com was originally reserved by programmer Jed McCaleb in 2006 as a website for users of the Magic: The Gathering Online to trade cards. The word mtgox was short for Magic: The Gathering Online eXchange. The site was sold to Mark Karpeles in March 2011 who served as the company CEO, after which the bitcoin started to go missing slowly.
Multi-Signature (MultiSig) // Multisignature
  1. Wallet which requires another party to authorize a transaction before it is broadcasted to the network.
  2. Is a security method when multiple network members have to authenticate a transaction.
  3. Multi-signature addresses allow multiple parties to require more than one key to authorize a transaction and the number of signatures is agreed upon at the creation of the address.
  4. A pubkey script that provides n number of pubkeys and requires the corresponding signature script provide m minimum number signatures corresponding to the provided pubkeys. Synonyms: Bare multisig Not To Be Confused With: P2SH multisig (a multisig script contained inside P2SH) || or || Advanced scripts that require multiple signatures without using OP_CHECKMULTISIG or OP_CHECKMULTISIGVERIFY
  5. Multi-signature addresses provide an added layer of security by requiring more than one key to authorize a transaction.
  6. Some cryptocurrency wallets and addresses are protected by multiple keys. Several people are required to approve (sign) transactions before they can take place.
  7. MultiSig is a permissions system for crypto wallets. The majority of cryptocurrency wallets are single-signature. This means you only need one person’s private key to control the balance within it. MultiSig means you need more than one private key to spend funds. This allows you to set up an M-of-M scheme. As an example, you might need 5 out of 9 signers to approve of a transaction for it to go through. This is useful for corporate wallets, where many owners and employees have to approve before a transaction is sent. Platforms like BitGo and Xapo provide MultiSig wallets for their users.
MultiChain
  1. MultiChain is some free software which people can download and run to design, deploy, and operate distributed ledgers that track ownership of digital tokens or assets.
  2. It is an open-source platform, based on the Bitcoin's Blockchain that can be applied to multi-asset financial transactions.
    Reference: BTA
N
Native Token
  1. A native token — a.k.a. native coin or native currency — is a token (see ‘token’ for a definition) that runs on it’s own blockchain and is ‘native’ to that network, offering some greater utilitarian or resourceful value within the network. Native tokens are often used within the network as an incentive for block validation or for a form of spam prevention in transaction costs. Examples of native tokens include BTC, ETH, NXT, etc. Native tokens are also referred to as ‘intrinsic tokens’ or ‘built-in tokens.’
nBits
  1. The target is the threshold below which a block header hash must be in order for the block to valid, and nBits is the encoded form of the target threshold as it appears in the block header. Synonyms: nBits || Target Not To Be Confused With: Difficulty (a number measuring the difficulty of finding a header hash relative to the difficulty of finding a header hash with the easiest target)
NEM (XEM)
  1. Refers to the cryptocurrency and the name of a platform for management of a variety of assets, including currencies, supply chains, ownership records, etc. It offers additional features to blockchain technology such as multi-signature accounts, encrypted messaging, etc
Neo (NEO)
  1. Refers to the cryptocurrency and the name of a China's first open source blockchain that was founded in 2014 by Da Hongfei. It is similar to Ethereum in its ability to execute smart contracts or dApps but has some technical differences such as coding language compatibility.
Node
  1. A node is any computer that connects to the blockchain network. Synonyms: Node || Full node || Archival node || Pruned node || Peer
  2. Node is defined as any computing device (computer, phone, etc.) that is participating in a network by way of receiving and sending data. Cryptocurrencies are supported by a network of computers each keeping a digital record of the data known as a blockchain. A computer, a phone, or any other computing device that can receive, transmit, and/or contribute to the blockchain is a node.
  3. A copy of the ledger operated by a participant of the blockchain network.
  4. A copy of the ledger operated by a participant with a blockchain network.
  5. A participant in the blockchain network. A node may participate in the mining process, consensus algorithm, or simply store a copy of the blockchain for querying.
    Reference: MIT
  6. A node is any computer that connects to the blockchain network. Essentially, it is a copy of the ledger operated by a participant of the blockchain network. All nodes need to be in agreement in order for a block to be added to the chain.
  7. A computer that possesses a copy of the blockchain and is working to maintain it. Child nodes point to parent nodes. So, nodes further “up the tree” are hashes of their respective children. Most hash trees implementations are binary, with each node under two child nodes. Though, more than two child nodes can be used under each node.
  8. A participant in a cryptocurrency network that provides a copy of the entire blockchain to the network. All miners host a node, but not all nodes have to mine cryptocurrency.
  9. Node (Full Node) Any computer that connects to the blockchain network is called a node. Nodes that fully enforce all of the rules of the blockchain (i.e., Bitcoin) are called full nodes. Most nodes on the network are lightweight nodes instead of full nodes, but full nodes form the backbone of the network
  10. A node is a computer running specific software which allows that computer to process and communicate pieces of information to other nodes. in blockchains, each node stores a copy of the ledger and information is relayed from peer node to the peer node until transmitted to all nodes in the network.
  11. Is a computer that contains the full current version of blockchain and participates in the mining process.
  12. Any computing server around the world can run as a cryptocurrency node, which can store a copy of the blockchain and serve to verify transactions.
Node Package Manager (NPM)
  1. Default package manager runtime environment node.js. NPM manages dependencies for an application
Nonce
  1. This is an arbitrary number that can only be used once and is often used with cryptographic systems in co-ordination with random number generators to improve security. They are also be used in co-ordination with blockcahin mining specifications to allow for variation in the difficulty of successfully mining a block.
  2. A number only used once in a cryptographic communication (often includes a timestamp)
  3. The nonce in a Bitcoin block is a 32-bit (4-byte) field whose value is set so that the hash of the block will contain a run of leading zeros. The rest of the fields may not be changed, as they have a defined meaning.
  4. A single-use arbitrary number generated for verification purposes to prevent replaying past transactions.
Nothing at Stake problem
  1. This is caused by validator nodes approving all transactions on old and new software after a hard fork occurs
O
Off-chain
  1. Transactions that occur off a given blockchain network, that may be later reported or batched together before submitted.
Off-Ledger Currency
  1. A digital currency that is created (minted) outside of the blockchain ledger but used on the blockchain ledger. Example: government currencies that get used on the blockchain.
Offline Storage
  1. Cryptocurrency wallets can be stored on devices and systems that are connected to the internet or not. Offline storage is the latter case, providing additional protection from hacking.
Ommer (aka Uncle)
  1. A block which has been completely mined but has not yet been added to the Blockchain.
On-chain governance
  1. A system for managing and implementing changes to a cryptocurrency blockchain
On-Ledger Currency
  1. A digital currency that is both created (minted) on the blockchain ledger and also used on the blockchain ledger. Most cryptocurrencies (like Bitcoin) are on-ledger currencies.
Online Storage
  1. Cryptocurrency wallets can be stored on devices and systems that are connected to the internet or not. Online storage is the former case, offers more convenience but also increased risk.
Open Source
  1. Collaborative and open software development approach that encourages experimentation and sharing. Project computer code is offered to others to work with and modify.
Oracle(s)
  1. A bridge from a blockchain to an external data source that allows a smart contract to complete its business by referencing timely real-world information. An oracle might allow a smart contract to access consumer energy usage, live train timetables, election results, and so on.
  2. For blockchain, an oracle is an automated system that decides based on pre-set rules and real-world events. It's an essential function that helps to arbitrate smart contracts.
  3. An agent that finds and verifies real-world occurrences and submits this information to a blockchain to be used by smart contracts.
  4. Oracles work as a bridge between the real world and the blockchain by providing data to the smart contracts.
  5. Oracles work as a bridge between the real world and the blockchain by providing data to the smart contracts. Smart contracts on the blockchain cannot access the outside network on their own. Therefore oracles sit between a smart contract and the external world, providing the data needed by the smart contract to prove performance while sending its commands to external systems.
  6. Smart contracts on the blockchain can not access the outside network on their own. Therefore oracles sit between a smart contract and the external world, providing the data needed by the smart contract to prove performance while sending its commands to external systems.
Orphan Block
  1. Blocks that are mined a little late and don’t form part of the main blockchain. In Bitcoin these are called ‘orphans’ and are entirely discarded, but in Ethereum they are called ‘uncles’ and can be referenced by later blocks.
  2. Blocks whose parent block has not been processed by the local node, so they can’t be fully validated yet. Synonyms: Orphan block Not To Be Confused With: Stale block
  3. Orphan describes a block that has been abandoned and will not be built upon. Blockchain is technology for creating permanent, secure digital recordings. If you imagine the blockchain as a book of records, then each page in that book is what is known as a “block”. A block is simply a recording of information. Blocks are attached to each other making what is known as the blockchain. Because many computers are maintaining the blockchain, occasionally two blocks are created at the same time. Since only one block can be created at a time, only one will be continued and built upon, the other block will be abandoned and is known as an orphan.
Output // Transaction Output // TxOut
  1. An output in a transaction which contains two fields: a value field for transferring zero or more satoshis and a pubkey script for indicating what conditions must be fulfilled for those satoshis to be further spent.
P
Paper Wallet
  1. A type of cold storage where private and public keys (and often a QR code) are printed or written on physical paper to prevent hacking and theft.
  2. The private key to an amount of bitcoin in a wallet, written or printed out on a piece of paper. This practice is considered a very secure way to keep your bitcoin as it is a form of cold wallet, and hence not connected to the Internet and subjected to threats of being stolen. However, it is still important to note that if your computer is infected with malware and connected online, the process of extracting your private key and viewing it to be copied or printed may still subject it to similar threats of being stolen. Precautionary measures will need to be taken, such as ensuring the computer is clean of any spyware and that it is not connected to the Internet. Paper wallet is still just a piece of paper document, and if not careful, may be misplaced or damaged. Once written or printed out, the paper wallet should be treated like cash or jewellery, and be safely stored in a bank vault or safe deposit box, especially if the private key grants access to a significant amount of bitcoin.
  3. A pair of public and private keys that individuals can print out onto a sheet of paper for safekeeping.
Participants
  1. A blockchain peer-to-peer network that is collectively owned and operated by a group of verified and identifiable participants such as individuals, institutions, business, universities, or hospitals.
Peer-to-Peer (P2P)
  1. Peer-to-peer refers to systems that work like an organized collective by allowing each individual to interact directly with the others. In the case of Bitcoin, the network is built in such a way that each user is broadcasting the transactions of other users. And, crucially, no bank is required as a third party.
  2. Refers to the decentralized interactions that happen between at least two parties in a highly interconnected network. P2P participants deal directly with each other through a single mediation point.
  3. A peer-to-peer network that distributes computing tasks among many, private computers (decentralized), instead of using company computers (centralized).
  4. Denoting or relating to computer networks in which each computer can act as a server for the others, allowing shared access to files and peripherals without the need for a central server
  5. Dealing directly through a single mediation point, participants of a Peer to Peer (P2P) network deal directly with each other using decentralized interactions in a highly interconnected network.
  6. Peer to peer or P2P is defined as a connection between two or more computers that allows them to directly share information, files, or other data. The word peer itself just means someone who is equal to another. Peers might share the same history, skills, power, etc. In a peer to peer network, there are no privileged peers with special rights or advantages. Every peer has the same rights and they all share the workload.
Pegged Currency
  1. A currency where the price is designed to remain the same as a designated asset. For example: 1 USDT is pegged to 1 USD. Also referred to as a stablecoin.
Permisionless
  1. Permisionless is a positive quality, where anyone is permitted to join and participate in an activity. Permissionless is oftne used when describing blockchain technologies because anyone can download the digital record known as the blockchain and participate in recording and verifying information.
Permissioned Blockchains
  1. Provide highly-verifiable data sets because the consensus process creates a digital signature, which can be seen by all parties.
Permissioned Ledger
  1. A large, distributed network using a native token, with access restricted to those with specific roles.
  2. A shared database with a blockchain structure that requires participants to obtain permission before reading or writing to the chain. Contrast this with permissionless blockchains, which anyone can join.
  3. Is a ledger where actors must have permission to access the ledger. Permissioned ledgers may have one or many owners. When a new record is added, the ledger’s integrity is checked by a limited consensus process. This is carried out by trusted actors — government departments or banks, for example — which makes maintaining a shared record much simpler than the consensus process used by unpermissioned ledgers.
Plasma
  1. An Ethereum off-chain scaling solution which may allow Ethereum to greatly increase the transactions per second capabilities.
  2. Plasma is a proposed framework for incentivized and enforced execution of smart contracts which is scalable to a significant amount of state updates per second (potentially billions) enabling the blockchain to be able to represent a significant amount of decentralized financial applications worldwide. These smart contracts are incentivized to continue operation autonomously via network transaction fees, which is ultimately reliant upon the underlying blockchain (e.g. Ethereum) to enforce transactional state transitions.
    Reference: https://plasma.io/
  3. In August 2017, Vitalik Buterin, the co-founder of Ethereum, and Joseph Poon, the designer of the Lightning Network, published a white paper. They described a new way to interlink blockchains through smart contracts. They named the architecture Plasma. The interlinked blockchains were to be placed in a hierarchy so that some were on top and therefore more authoritative than others. Parent blockchains launch child blockchains. A child blockchain can also launch their own child blockchains. Poon described the structure as similar to that of a court system. The lower level has many courts, while the higher levels have fewer. At the highest point is the supreme court. Lower courts handle the bulk of the cases. The supreme court handles only what the lower courts cannot solve, or they give direction to the lower courts on how to solve cases. The main parent blockchain is only consulted when disputes arise among child blockchains. This main blockchain is the ultimate truth source of the system and also facilitates the sharing of data and digital value in the system running on top of it.
Ponzi Scheme
  1. A scam in which new investors' funds are used to pay returns promised to previous investors. Do not invest in these (example, Bitconnect).
Practical Byzantine Fault Tolerance (PBFT)
  1. Practical Byzantine Fault Tolerance (PBFT) was introduced by Miguel Castro and Barbara Liskov at the MIT Laboratory for Computer Science in 1999. PBFT is one of the potential solutions to the Byzantine Generals’ Problem. With PBFT, the goal is to decide whether to accept a piece of information submitted to the blockchain or not. Each party (“general”) maintains an internal state. When a party receives a message, they use the message with their internal state to run a computation. This computation will lead to this party’s decision about the message. Then, the party will share the decision with all other parties in the network. The final decision is determined based on the total decisions from all parties. A high hashrate is not required in this process because PBFT relies on the number of nodes to confirm trust. Once enough responses are reached, the transaction is verified to be a valid transaction. Some blockchain projects are using PBFT as their algorithm, such as Stellar, Hyperledger, and Ripple.
  2. The Byzantine Generals Problem is a term etched from the computer science description of a situation where involved parties must agree on a single strategy to avoid complete failure, but where some of the involved parties are corrupt and disseminating false information or are otherwise unreliable.
    Reference: MIT
Pragma(s) or Pragma-line
  1. Defines which compiler version the smart contract uses
Pre-mine
  1. A practice with certain altcoins where the creator generates a number of altcoins before the network goes live for the first for proper mining by legitimate miners. Some scams involving altcoins start off with a pre-mined quantity of bitcoin by the creator, although it may be legitimate if the nature of the altcoin requires that it be pre-mined, or if the altcoin only serves a specific industry on a small scale. In any case, the creator should be expected to declare this upfront so that investors and users know what they are getting the altcoins for.
Pre-Sale
  1. A sale that starts before an Initial Coin Offering (ICO) is available to the general public.
Private Blockchains
  1. Private blockchains are private because of the genesis block they are using. Their blocks do not match with any other blockchains.
  2. A fully private blockchain is a blockchain where write permissions are kept centralized to one organization. Read permissions may be public or restricted to an arbitrary extent. Likely applications include database management, auditing, etc. internal to a single company, and so public readability may not be necessary in many cases at all, though in other cases public auditability is desired
  3. Blockchain that can control who has access to it. Contrary to a public blockchain a Private Blockchain does not use consensus algorithms like POW or POS, instead they use a system known as byzantine fault tolerant(BFT). BFT is not a trustless system which makes a BFT system less secure.
  4. A private blockchain keeps write permissions centralized within an organization and read permissions may be public or have arbitrary restrictions applied. The most common uses of a private blockchain include database management, auditing, financial management, and other internal services that are not required to have external access. In some cases, public readability is provided for the sake of auditability.
  5. A closely controlled network operated by consortia in which the data is confidential and is accessed only by trusted members. Private blockchains do not require a token.
  6. A private blockchain is simply one that is not publicly accessible. You can think of this as the difference between the internet and a private network. Usually, you need to have some sort of access code or key in order to participate in or even view a private blockchain.
Private Key
  1. A private key in cryptography is the secret that is used prevent unauthorized access to certain data or systems. In blockchain systems, the private key is usually used to control access to cryptocurrency tokens such as bitcoin or factoids. Protecting your private keys is critical, as failing to do so will leave your systems, data, or wallets exposed.
  2. A private key is a string of data that allows you to access the tokens in a specific wallet. They act as passwords that are kept hidden from anyone but the owner of the address. Private keys must never be revealed to anyone but you, as they allow you to spend the coins from your coin wallet through a cryptographic signature. There are different types of wallets such as online wallets, mobile wallets, desktop wallet, hardware wallets or paper wallets. The category of each wallet is determined by where private keys are stored. Online wallets are mostly provided by exchanges and keep user’s private keys on their servers. If the service provider goes offline users would lose access to their funds. Hardware wallets for example store user’s private keys in a secure device which looks like a USB flash drive.
  3. A string of letters and numbers that are used for sending cryptocurrency. The private key should be kept secret because it enables spending with the cryptocurrency wallet.
  4. A private key is a string of data that shows you have access to bitcoins in a specific wallet. Private keys can be thought of as a password; private keys must never be revealed to anyone but you, as they allow you to spend the bitcoins from your bitcoin wallet through a cryptographic signature.
  5. Each time a user runs a cryptocurrency wallet for the first time a public-private key pair gets generated. The private key is a randomly generated number which allows users to transact over the blockchain. It is locally stored and kept secret. Each time a Bitcoin gets sent a private key has to sign the transaction. This action is automatically executed by the wallet software. When a wallet asks users to do a backup what this means is that the users must secure their private key. There are different types of wallets such as online wallets, mobile wallets, desktop wallet, hardware wallets or paper wallets. The category of each wallet is determined by where private keys are stored. Online wallets are mostly provided by exchanges and keep user’s private keys on their servers. If the service provider goes offline users would lose access to their funds. Hardware wallets for example store user’s private keys in a secure device which looks like a USB flash drive.
  6. A unique string of data that represents proof of identification within the blockchain, including the right to access and own that participant’s wallet within a cryptocurrency. It must be kept secret: it is effectively a personal password.
  7. The private portion of a keypair which can create signatures that other people can verify using the public key.
  8. A private key is a secret piece of data that proves your right to spend bitcoins from a specific wallet through a cryptographic signature. Your private key(s) are stored in your computer if you use a software wallet; they are stored on some remote servers if you use a web wallet. Private keys must never be revealed as they allow you to spend bitcoins for their respective Bitcoin wallet.
Private Sale
  1. An early stage investment round for strategic investors with a considerable amount of investible funds.
Proof of Activity
  1. Active Stakeholders who maintain a full node are rewarded
Proof of Authority (PoA)
  1. Is a consensus mechanism in a private blockchain which essentially gives one client (or a specific number of clients) with one particular private key the right to make all of the blocks in the blockchain
  2. A Proof of authority is a consensus mechanism in a private blockchain which essentially gives one client(or a specific number of clients) with one particular private key the right to make all of the blocks in the blockchain.
  3. A private key that gives the holder the right to create the blocks in a private blockchain. It can be held by a single entity or a set number of entities. This is an alternative to the Proof of Work model, as instead of getting multiple random Nodes to approve a transaction, a group of specific Nodes given the authority can approve. This is a far faster method.
Proof of Burn (PoB)
  1. A consensus distribution algorithm that rewards earnings based on the proof of a miners that they burned some coins – that is, sent them to a verifiably unspendable address.
  2. Miners send coins to an inactive address essentially burning them. The burns are then recorded on the blockchain and the user is rewarded.
  3. Value from one cryptocurrency can be transferred to another through the proof-of-burn protocol. This means that a node participates in a lottery to decide the status of the blockchain by burning value they already hold in the form of another cryptocurrency such as bitcoin or ether. To find the next block, the node sends bitcoin, ether or any other cryptocurrency to an unspendable address. In exchange, the node receives a reward in the currency native to the blockchain it helps to maintain. The first blockchain to successful apply the proof-of-burn protocol for mining was Slimcoin. Its network combines proof of burn with proof of work and proof of stake, making it the first cryptocurrency to combine three protocols.
Proof of Capacity (PoC) // Proof of Space
  1. Plotting your hard drive (storing solutions on a hard drive before the mining begins). A hard drive with the fastest solution wins the block
  2. With the proof-of-capacity (PoC) consensus mechanism, instead of using computing power or stake in coins, blockchains have the option to let nodes in the network use their available hard drive space. This mining protocol is useful especially in networks that facilitate the sharing of memory space. The more hard drive space a node has, the more say it has in the maintenance of the ledger. The nodes also receive rewards in the form of the native coins, depending on how much space the nodes make available to the network. Networks that use this protocol include Storj, Sia and Filecoin.
Proof of Elapsed Time
  1. Consensus algorithm in which nodes must wait for a randomly chosen time period and the first node to complete the time period is rewarded
Proof of Importance (PoI)
  1. This is again a variation of PoS, it tries to overcome the problem of ‘rich getting richer’ in PoS, rich are more likely to sign the next block, and the more blocks they obtain, the richer they get. The problem is the same, richer users will gain wealth much faster than others making system centralised. POI system not only rewards those with a large account balance, but also takes into account the frequency i.e. how much they transact to others and who they transact with. This is how it works: Each user is given a trust score, the higher it is, the more chance they have of being rewarded. Trust score is calculated based on vested coin balance and frequency of the transactions. Rewarding is done through harvesting, a mining process in which a node will calculate blocks and they are added to the blockchain.
Proof of Stake // PoS // Proof-of-Stake
  1. For Proof of Stake, miners still process and validate transactions, but do so by proving that they have ownership of a certain amount of the asset, rather than by performing energy-intensive computations. For PoS, miners “lock up” their assets (that’s the “stake”) and then promise to fairly process transactions: If they do an honest job, they get rewarded with transactions fee payments, but if they try to cheat, they get penalized and lose some or all of their locked assets. So in short, this system financially incentives honest behavior. Proof of Stake is designed to be more environmentally friendly than Proof of Work.
  2. With Bitcoin’s high cost of mining, blockchain developers sought cheaper alternatives that didn’t require burning high amounts of energy. The first of these alternatives is proof of stake (PoS), which allocates the level of responsibility in maintaining the public ledger to a node according to the number of coins it holds. The more coins a node holds, the more chances it has of being picked to update the ledger. Since POS requires neither burning of energy nor specialized hardware, it is one of the cheapest blockchain consensus protocols. It is also one of the most inclusive, as all coins holders in a network stand a chance to participate in the mining process. Blockchain networks that use proof of stake include Peercoin, Nem and Dash. Ethereum is also planning to move its protocol from proof of work to proof of stake when it adopts its Casper system.
  3. Is an alternative to the proof-of-work system, in which your existing stake in a cryptocurrency (the amount of that currency that you hold) is used to calculate the amount of that currency that you can mine.
  4. Is a security method in cryptocurrency, and a tool of achieving consensus in which there is a greater chance of creating a new block. The profit will be achieved by the users with a large amount of coins in the account.
  5. A novel consensus protocol in which, instead of mining, nodes can validate and make changes to the blockchain on the basis of their existing economic stake.
  6. Proof-of-stake (PoS) is a method by which a cryptocurrency blockchain network aims to achieve distributed consensus. While the proof-of-work (PoW) method asks users to repeatedly run hashing algorithms or other client puzzles, to validate electronic transactions, proof-of-stake asks users to prove ownership of a certain amount of currency (their “stake” in the currency). Peercoin was the first cryptocurrency to launch using proof-of-Stake. Other prominent implementations are found in BitShares, Nxt, BlackCoin, NuShares/NuBits and Qora. Ethereum has planned a hard fork transition from PoW to PoS consensus. Decred hybridizes PoW with PoS and combines elements of both in an attempt to garner the benefits of the two systems and create a more robust notion of consensus. With Proof of Work, the probability of mining a block depends on the work done by the miner (e.g. CPU/GPU cycles spent checking hashes). In the case of Bitcoin, with Proof of Stake, the resource that’s compared is the amount of Bitcoin a miner holds – someone holding 1% of the Bitcoin can mine 1% of the “Proof of Stake blocks”. Instead of sacrificing energy to mine a block, a user must prove they own a certain amount of the cryptocurrency to generate a block. The more stake you own, the more likely you are to generate a block. In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy. Proof of Stake sounds like a good idea, but ironically, there is the “Nothing at Stake” problem. Since mining Bitcoins is costly, it is not smart to waste your energy on a fork that won’t earn you any money, however with Proof of Stake, it is free to mine a fork.d
  7. Proof-of-Stake is an alternative to the Proof-of-Work system, in which your existing stake in a cryptocurrency (the amount of that currency that you hold) is used to calculate the amount of that currency that you can mine. The more stake you own, the more likely you are to generate a block. In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy. Proof of Stake sounds like a good idea, but ironically, there is the “Nothing at Stake” problem. Since mining Bitcoins is costly, it is not smart to waste your energy on a fork that won’t earn you any money, however with Proof of Stake, it is free to mine a fork.
  8. A consensus algorithm that chooses the owner of a new block based on the wealth they have or (Stake). There is not a block reward so the forgers take the transaction fee.
  9. POW requires extensive energy consumption. Over the past a few years, the rising value of bitcoin boosted the demand for GPU. Some chip companies create custom chips solely for mining. Unlike POW, POS is based on the participants’ coin stake. The more coins the staker has, the more likely the staker will add a new block of the transaction to the blockchain. There’s no block reward in POS. The staker’s rewards are only the transaction fee. Because of lower energy-intensive compared to POW, POS system is suited for platforms with static coin supply. Most crowdsale-funded platforms leverage this approach to distributing tokens based on investment.
  10. The mechanism by which participants earn the right to add new blocks and so earn new tokens, based on how much of that currency they already hold.
  11. Another alternative to Proof of Work, this caps the reward given to miners for providing their computational power to the network, at that miner’s investment in the cryptocurrency. So if a miner holds three coins, they can only earn three coins. The system encourages miners to stick with a certain blockchain, rather than converting their rewards to an alternate cryptocurrency.
  12. A consensus distribution algorithm that rewards earnings based on the number of coins you own or hold. The more you invest in the coin, the more you gain by mining with this protocol.
  13. A novel consensus protocol in which, instead of mining, nodes can validate and make changes to the blockchain based on their existing economic stake.
    Reference: MIT
  14. An algorithm that rewards participants that solves difficult cryptographic puzzles to achieve distributed consensus. Unlike proof of work or PoW, a person can validate transactions and create new blocks based on their individual wealth (i.e. stake) such as the total number of coins owned. One of the key advantages that PoS has over PoW is lower energy consumption.
  15. Proof-of-stake pushes people who own a selection of a blockchain’s tokens to make decisions on validating the chain. In practice, it’s a much less energy-intensive practice than mining.
Proof of Work // PoW
  1. Proof-of-Work is a consensus distribution algorithm that ties mining capability to computational power and requires an active role in mining data blocks, often consuming resources, such as electricity. The more ‘work’ you do or the more computational power you provide, the more coins you are rewarded with. Blocks must be hashed, which is in itself an easy computational process, but an additional variable is added to the hashing process to make it more difficult. When a block is successfully hashed, the hashing must have taken some time and computational effort. Thus, a hashed block is considered proof-of-work.
  2. Is a system that ties mining capability to computational power. Blocks must be hashed, which is in itself an easy computational process, but an additional variable is added to the hashing process to make it more difficult. When a block is successfully hashed, the hashing must have taken some time and computational effort. Thus, a hashed block is considered proof of work.
  3. A hash below a target value which can only be obtained, on average, by performing a certain amount of brute force work—therefore demonstrating proof of work.
  4. A consensus distribution algorithm that requires an active role in mining data blocks, often consuming resources, such as electricity. The more ‘work’ you do or the more computational power you provide, the more coins you are rewarded with.
  5. Repeatedly running a hash function, the mechanism by which data miners win the right to add blocks to a bitcoin-style blockchain.
  6. Is the principle of distributed systems protection and a tool for achieving consensus, in which the size of remuneration depends on the computational resources of the miner – the greater is the computational work performed by the network participant, the greater remuneration is received.
  7. POW is the first and most well-known consensus mechanism and invented by Bitcoin’s founder, Satoshi Nakamoto. In POW, a miner who finds the hash first will be allowed to add a new block of the transaction to the blockchain. The process of mining is extremely computation-intensive, so having a high hashrate is the key for miners to calculate the hash, thus getting the rewards. Besides Bitcoin, Ethereum is also using POW as a part their algorithm. However, what makes Ethereum different is their proof of stake (POS)-based finality system capable of overlaying an existing POW blockchain, resulting in a hybrid POW/POS system called Casper Friendly Finality Gadget (FFG).
  8. In order to receive a reward for mining a cryptocurrency, the miner must show that their computer contributed effort to approve a transaction. A variable is added to the process of hashing a transaction that demands that effort before a block can be successfully hashed. Having a hashed block proves the miner did work and deserves a reward – hence Proof of Work.
  9. A consensus algorithm which requires a user to “mine” or solve a complex mathematical puzzle in order to verify a transaction. “Miners” are rewarded with Cryptocurrencies based on computational power.
  10. PoW system/protocol/function is an economic measure to deter denial of service attacks and other service abuses such as spam on a network by requiring some work from the service requester, usually meaning processing time by a computer. The concept may have been first presented by Cynthia Dwork and Moni Naor in a 1993 journal. The term “Proof of Work” was first coined and formalized in a 1999 paper by Markus Jakobsson and Ari Juels. A key feature of these schemes is their asymmetry: the work must be moderately hard (but feasible) on the requester side but easy to check for the service provider. This idea is also known as a CPU cost function, client puzzle, computational puzzle or CPU pricing function
  11. For Proof or Work, so-called “miners” process transactions by using computers to solve complicated mathematical puzzles. They “proof” that they did this computational work by finding solutions to those puzzles. By doing this, they help validate and process transactions and in turn, are paid for their work with transactions fees and with newly created coins.
  12. The consensus protocol of choice for Bitcoin and many other cryptocurrencies. To add a new block, miners must calculate a hash for it that meets certain narrow criteria. Doing so requires an enormous number of random guesses, making it a costly process that deters attempts to commit fraud.
  13. An algorithm that rewards the first person that solves a computational problem (i.e. mining) to achieve distributed consensus. Miners compete to solve difficult cryptographic puzzles in order to add the next block on the blockchain. It prevents spam and cyber attacks such as DDoS as it requires work (i.e. processing time) from the service requester.
  14. The consensus protocol of choice for bitcoin and many other cryptocurrencies. To add a new block, miners must find an input to a hash function so that the output of the hash function meets certain narrow criteria. Doing so requires an enormous number of random guesses as inputs to the hash function, making it a costly process that deters attempts to commit fraud.
    Reference: MIT
  15. Proof of work (PoW) is the consensus mechanism used by Bitcoin. As the name suggests, the mechanism requires nodes to prove they have done work to receive the right to add new transactions to the blockchain. The work is energy intensive, as it involves the nodes hashing data through high-performance, application-specific integrated circuit (ASIC) chips. In the competition to solve cryptographic puzzles, those with most efficient hardware have the upper hand. Bitcoin has gone from mining using CPUs on desktops to using ASICs in specially designed mining rigs. The high cost of electricity and the initial capital needed to acquire the appropriate mining hardware makes blockchain networks that use PoW, such as Bitcoin, difficult to join. Aside from Bitcoin, other blockchain networks that use PoW include Ethereum, Ethereum Classic and Litecoin.
  16. Bitcoin mining is resource intensive due to the amount of computing power that is required to mine a single block. Miners are able to prove the amount of computing power that they used to solve a particular block with the hashcash proof-of-work function. This system of proving one’s worth to the Bitcoin mining ecosystem uses cryptography to show that a single miner completed a certain amount of work on their computer. The easiest way to explain proof-of-work is to imagine that it takes a certain amount of computing power to solve a mathematical equation. To find the solution to a certain equation related to a new block, a computer must have completed a certain number of computations. These equations have become much harder to solve as more hashing power has been added to the Bitcoin network over time.
Protocols
  1. Protocols are sets of formal rules describing how to transmit or exchange data, especially across a network. Public Blockchains A public blockchain is a blockchain that anyone in the world can read, anyone in the world can send transactions to and expect to see them included if they are valid, and anyone in the world can participate in the consensus process – the process for determining what blocks get added to the chain and what the current state is. As a substitute for centralized or quasi-centralized trust, public blockchains are secured by crypto economics – the combination of economic incentives and cryptographic verification using mechanisms such as proof of work or proof of stake, following a general principle that the degree to which someone can have an influence in the consensus process is proportional to the quantity of economic resources that they can bring to bear. These blockchains are generally considered to be “fully decentralized”.
Pseudonymity
  1. Bitcoin is pseudonymous. In Bitcoin, your pseudonym is the address to which you receive Bitcoin. Every transaction involving that address is stored forever in the blockchain. If your address is ever linked to your identity, every transaction will be linked to you.
Pseudorandom
  1. The property of a definite function that can produce an outcome that passes statistical tests of randomness.
Public Address
  1. Public Addresses are a cryptographic hash of a public key. These can be published anywhere unlike private keys.
Public Blockchains
  1. A public blockchain is a blockchain that anyone in the world can read, anyone in the world can send transactions to and expect to see them included if they are valid, and anyone in the world can participate in the consensus process – the process for determining what blocks get added to the chain and what the current state is. As a substitute for centralized or quasi-centralized trust, public blockchains are secured by crypto economics – the combination of economic incentives and cryptographic verification using mechanisms such as proof of work or proof of stake, following a general principle that the degree to which someone can have an influence in the consensus process is proportional to the quantity of economic resources that they can bring to bear. These blockchains are generally considered to be “fully decentralized”
  2. A large distributed network using a native token (such as bitcoin), open to everyone to participate and maintain.
Public Key
  1. A string of letters and numbers that are used to receive cryptocurrency. Works similar to a traditional bank account number and can be shared publicly with others.
  2. The public portion of a keypair which can be used to verify signatures made with the private portion of the keypair.
  3. A unique string of data that identifies a participant within the blockchain. It can be shared publicly.
  4. Is a cryptographic public key hash. It functions as an e-mail address, and unlike secret keys can be provided to third parties.
  5. Each time a user runs a cryptocurrency wallet for the first time a public-private key pair gets generated. The private key is a randomly generated number which allows users to transact over the blockchain. It is locally stored and kept secret. Each time a Bitcoin gets sent a private key has to sign the transaction. This action is automatically executed by the wallet software. When a wallet asks users to do a backup what this means is that the users must secure their private key. There are different types of wallets such as online wallets, mobile wallets, desktop wallet, hardware wallets or paper wallets. The category of each wallet is determined by where private keys are stored. Online wallets are mostly provided by exchanges and keep user’s private keys on their servers. If the service provider goes offline users would lose access to their funds. Hardware wallets for example store user’s private keys in a secure device which looks like a USB flash drive.
  6. A cryptographic key that can be obtained and used by anyone to encrypt messages intended for a particular recipient, such that the encrypted messages can be deciphered only by using a second key that is known only to the recipient (the private key ).
  7. A public key is derived from a private key and allows you to "lock" digital systems. An administrator can set rules so that only those who have the private key matching the public key will be allowed access. A public key is safe to share because you it is created using an irreversible mathematical equation. You can validate a private key using a public key, but you can't determine what the private key is using the public key alone. In cryptocurrency systems, a public key usually refers to your address where tokens (think bitcoin or factoids) can be sent to you.
Public Key Cryptography
  1. A cryptographic system that uses both a private key and public key to safeguard transactions. It's the central security-layer behind cryptocurrencies like Bitcoin.
  2. Encryption that uses two mathematically related keys. A public and private key. It is impossible to derive the private key based on the public key.
  3. Public-key cryptography is a pair of keys used by a cryptographic system consisting of a public key and a private key. A public key may be circulated between many users, whereas a private key is known to the owner exclusively. There are two functions accomplished by public-key cryptography, public-key encryption (privacy) and digital signatures (authentication).
    Reference: MIT
Public Key Encryption
  1. One of two functions involved in public-key cryptography (see definition). Public-key encryption is a pair of cryptographic algorithms that can be used to privately send messages over public channels. The encryption algorithm takes the public key and a message as input and produces a scrambled/encrypted ciphertext. The decryption algorithm takes the private key and the ciphertext as input and outputs the message in clear text.
    Reference: MIT
Pump and Dump Schemes
  1. Investment scheme that advertises the benefits of a certain asset, with the hope that a lot of people buy it and raise the price. The asset is then sold by the originator for profit.
  2. A scheme in which the development team (or short-term traders) hypes up a project without fundamental basis in order to pump up the price of the tokens temporarily and then sells their holdings immediately after launch to earn a profit.
  3. A scheme in which the development team (or short-term traders) hypes up a project without fundamental basis in order to pump up the price of the tokens temporarily and then sells their holdings immediately after launch to earn a profit. See the US SEC's investor alert on pump and dump schemes.
Q
QR Code
  1. A machine-readable label that shows information encoded into a graphical black-and-white pattern. For cryptocurrencies, often used to easily share wallet addresses with others.
Quantum Computing // Cryptography
  1. This is an emerging field of computing research that utilises quantum mechanics to perform certain calculations faster than traditional computers. Some fear that this could allow for hacking cryptocurrencies in the future by allowing anyone to generate the private key from a known public key.
  2. Quantum computing works using particles that can be in superposition. These particles represent qubits instead of bits and can take the value of 1, 0 or both simultaneously. Quantum computers are mainly theoretical but can outclass modern computers if brought to the mainstream.
Quantum Resistance (Quantum Secure)
  1. Quantum computers are next-generation computers that have the potential to circumvent commonly used cryptography schemes used by blockchains. Bitcoin uses a technology called “elliptic curve signature scheme” to secure its system. IOTA does not use the elliptic curve cryptography (ECC) but it uses hash-based signatures. This is different than Bitcoin because it makes its protocol resistant against by Quantum Computers but also simpler and faster for signing and verifying transactions. IOTA claims they are quantum-resistant because of “Winternitz signatures.”
R
R3 Corda
  1. Corda is a distributed ledger platform designed from the ground up to record, manage and synchronise financial agreements between regulated financial institutions. R3 refers to the consortium of more than 70 of the world’s biggest financial institutions in research and development of blockchain database usage in the financial system.
Race Attack
  1. When two transactions are created with the same funds at the same time, with the intention of spending those funds twice.
Raiden Network
  1. An upcoming protocol change to the Ethereum blockchain that is designed to allow for high-speed transfers and better scaling. Similar to Bitcoin's proposed Lightning Network.
Rekt
  1. This is a misspelling of ‘wrecked’. This term refers to a trader or investor who is utterly ruined and destroyed with losses from the current downfall of a price.
Relative Strength Index
  1. A type of technical analysis whereby you determine the momentum of price change over time. It looks at recent changes in price exponentially, with the most recent changes given more weight than older ones. This produces an overall trend of movement for a cryptocurrency that can determine if the market is Overbought (a reading higher than 70) or Oversold (a reading lower than 30).
Remittance
  1. A sum of money being sent, usually internationally, as a payment or gift.
Replicated Ledger
  1. A blockchain ledger (see above) with one main copy of the data (master ledger), connected to a set of sub-layers of the same data (slave ledgers).
Resistance
  1. Resistance levels are price points that are likely to see a rising cryptocurrency lose steam and perhaps stage a reversal downwards. If a coin has demonstrated difficulty edging past a certain price, that price would become a resistance level.
Return on Investment (ROI)
  1. The percentage gain that was made with an investment or asset. For example, a 100% ROI means that the price of the asset or investment has doubled in value.
Ring Signature
  1. Ring signature is a cryptographic technology that could provide a decent level of anonymization on a blockchain. Ring signatures make sure individual transaction outputs on the blockchain can’t be traced. A message signed with a ring signature is endorsed by someone in a particular group of people. One of the security properties of a ring signature is that it should be computationally infeasible to determine which of the group members’ keys was used to produce the signature.
  2. Using individual transaction outputs on the blockchain, that can’t be traced, Ring Signature is a cryptographic technology that provides a level or anonymisation. Messages signed with a ring signature is endorsed by an individual or an organisation. Ring signatures provide security by making it impossible to determine which group member’s key was used to produce the signature.
Ripple (XRP)
  1. Refers to the cryptocurrency and the name of an open source payment platform where the cryptocurrency (Ripple or XRP) can be transferred. The vision for the platform is to enable real-time global payments anywhere around the world. The Ripple payment protocol was built by OpenCoin which was founded in 2012.
  2. A Blockchain payment system for banks, payment providers, digital asset exchanges, and other companies. Designed to move large amounts of money more quickly and reliably.
  3. Ripple is a payment network built on distributed ledgers that can be used to transfer any currency. The network consists of payment nodes and gateways operated by authorities. Payments are made using a series of IOUs, and the network is based on trust relationships.
Routing Attack
  1. An attack on the Internet Service Provider level to affect uptime or participation in a web-enabled system, such as a blockchain.
S
Satoshi
  1. Denominations of Bitcoin value, usually measured in fractions of a bitcoin but sometimes measured in multiples of a satoshi. One bitcoin equals 100,000,000 satoshis.
  2. The smallest unit of Bitcoin, equal to 0.00000001 BTC.
  3. Named after the creator of Bitcoin, a Satoshi is the smallest unit of measure of the cryptocurrency. Each Satoshi is 0.00000001 Bitcoin, making the currency very divisible.
  4. The smallest unit of bitcoin that can currently be sent: 0.00000001 BTC, that is, a hundredth of a millionth BTC.
    Reference: MIT
Satoshi Nakamoto
  1. The mysterious creator of Bitcoin. Even though Bitcoin was created in 2008, to this day nobody knows his or her true identity. Satoshi could be a woman, a man, or a group.
  2. Is a person or group of people who created the bitcoin protocol and reference software, Bitcoin Core (formerly known as Bitcoin-Qt). In 2008, Nakamoto published a paper on The Cryptography Mailing list at metzdowd.com describing the bitcoin digital currency. In 2009, they released the first bitcoin software that launched the network and the first units of the bitcoin cryptocurrency, called bitcoins.
  3. We speculate that Satoshi Nakamoto is a person or group of people who created the bitcoin protocol and reference software, Bitcoin Core (formerly known as Bitcoin-Qt). In 2008, Nakamoto published a paper on The Cryptography Mailing list at metzdowd.com describing the bitcoin digital currency. In 2009, Satoshi released the first bitcoin software that launched the network and the first units of the bitcoin cryptocurrency, called Bitcoins.
  4. Is a person (or a group of people) known as the creator of the bitcoin currency and the original bitcoin client. He is still unknown.
  5. The name used by the unknown person or persons who designed the Bitcoin protocol.
    Reference: MIT
Scalability
  1. A change in size, or scale, to handle the ongoing demand for blockchain network resources.
  2. The capacity of a blockchain to be changed in size or scale.
Schnorr
  1. A large Bitcoin update brewing as of the time of drafting for this article, Schnorr proposes to give users a new way to generate the private and public keys critical to cryptocurrencies. It replaces the Elliptic Curve technique currently used to generate keys with the Schnorr technique. This update increases both privacy and security by grouping together MultiSig and regular transactions in the same category, allowing the blockchain process to more transactions and hiding whether or not a transaction is MultiSig or not.
Script
  1. Is the name of the Bitcoin protocol’s scripting system that processes and validates transactions. Script is a clever, stack-based instruction engine, and it makes all transactions from simple payments to complex oracle overseen contracts possible.
Scrypt
  1. Is an alternative proof of work system to SHA-256, designed to be particularly friendly to CPU and GPU miners, while offering little advantage to ASIC miners.
  2. Scrypt is a type of cryptographic algorithm and is used by Litecoin. Scrypt creates a lot of pseudorandom numbers that need to be stored in a RAM location. Generating the numbers is computationally intensive and as they are accessed a few times it makes sense to use RAM in conjunction with hashing power (see Hash Rate) rather than generating them on the fly – a time and memory trade off in terms of optimizing speed. Compared to SHA-256 (see SHA-256), this is quicker as it does not use up as much processing time. It was designed to be particularly friendly to CPU and GPU miners, while offering little advantage to ASIC miners (see ASIC).
SDK
  1. A software development kit provides the necessary tools for a developer to create software on a specific platform
SEC
  1. Short for Securities and Exchange Commission. A United States government agency that regulated securities (stocks, bonds, etc.) as well as stock exchanges.
Secure Hash Algorithm (SHA)
Security Token
  1. A security token is a token that acts as a security and doesn’t have usability at the time of its release. It is primarily aimed at investors and is a tradable asset. Many ICOs also release security tokens in the hope that they will raise funds from the market. Security tokens have to meet federal security regulations to be in circulations. This is done to ensure that that the ICOs that use security tokens for raising funds are legit.
Seed Phrase
  1. Seed Phrases are a special string of characters generated upon creating a wallet that allow recovery of the wallet in the event that access to the wallet is lost.
Segregated Witness (SegWit)
  1. A process where the transaction signatures are separated from bitcoin transactions. Allowing more transactions to fit within one block.
  2. A proposed change to Bitcoin's blockchain that would increase the block size limit from 1MB to 2MB for faster transactions. The implementation would be a fork (see above).
  3. The process where the block size limit on a blockchain is increased by removing digital signature data and moving it to the end of a transaction to free up capacity. Transactions are essentially split (or 'segregated'), into two segments: the original data segment and the signature (or 'witness') segment. SegWit removes the malleability risk from the main blockchain and checks it before a transaction becomes a part of the blockchain and has all its information added to the blockchain, making the information irreversible. SegWit makes it possible to track bitcoin spending in an easy way, which is looking transactions up using their transaction identifiers.
  4. Segregated Witness, or SegWit in short, is a soft fork solution that addresses the scalability issue as transactions on the Bitcoin network increases over time. SegWit allows the signature part of bitcoin transactions to be separate from the transfer, resulting in a smaller transaction size. This means that more transactions could be fitted into a block regardless of the block size. SegWit also introduces some security improvements, such as fixing the transaction malleability problem where transaction IDs could be modified. This would make it easier for wallet owners to track their spent bitcoin and prevent follow-up transactions from becoming invalid due to an earlier payment or transaction ID getting modified. With this malleability issue resolved, the Lightning Network will also be less complicated to implement as there will now be more efficient use of space on the blockchain. See also, Lightning Network.
  5. Segmented Witness (or SegWit) is a soft fork that happened with the Bitcoin blockchain. It solved congestion on the network by increasing the blockchain’s block size limit and splitting blocks of data in two. It separated out the unlocking signature with the scripts that send and receive data with the transactional data. This allows the network to process more transactions per second. Users don’t have to wait as long for bitcoin transactions.
Sell Wall // Buy Wall
  1. Using a depth chart, traders can see the current limit buy and sell points. The graphical representation on the depth chart looks like walls: http://media.coindesk.com/uploads/2015/05/image-1.png
Serenity
  1. Serenity is the fourth and final phase of Ethereum. Because PoW (Proof of Work) entails an enormous waste of energy, the developers want to find an alternative in this phase. The Ethereum Network is expected to be converted from PoW to PoS (Proof of Stake). Apart from this, the network should be faster, more efficient, easier for beginners and more resilient against the closure of mining capacity. As with Bitcoin, Ethereum mining requires a massive amount of energy; rough estimations put energy use at levels similar to the entire nation of Estonia. By switching to PoS, it becomes possible for individuals to perform mining by connecting to a computer network, thereby reducing consumption. According to Alex de Vries, energy consumption after the switch to Proof of Stake will fall to near negligible levels.
SHA-256
  1. A very strong cryptographic standard that is used as the basis for Bitcoin's and other proof of work systems (see above). It is also the technology that protects wallets.
  2. SHA-256 is a cryptographic algorithm used by cryptocurrencies such as Bitcoin. However, it uses a lot of computing power and processing time, forcing miners to form mining pools to capture gains.
  3. Is an encryption algorithm that underlies the bitcoin and some other cryptocurrencies mining.
  4. Is the cryptographic function used as the basis for bitcoin’s proof of work system.
Sharding
  1. Dividing a blockchain into several smaller component networks called shards capable of processing transactions in parallel.
  2. A scaling solution for blockchains to improve high-volume transaction speeds. Instead of every node (see above) holding a full blockchain copy, they only hold partial copies.
  3. A scaling solution for blockchains. Typically, every node in a blockchain network houses a complete copy of the blockchain. Sharding is a method of splitting a large piece of data into smaller pieces, each of which are called a shard, and each shard can only transact with other accounts in the same shard. This allows nodes to have partial copies of the complete blockchain in order to increase overall network performance and consensus speeds. When speaking about shards, Vitalik Buterin explained them this way, “Imagine that Ethereum has been split into thousands of islands. Each island can do its own thing. Each of the island has its own unique features and everyone belonging on that island, i.e. the accounts can interact with each other AND they can freely indulge in all its features. If they want to contact with other islands, they will have to use some sort of protocol.”
  4. Sharding is defined as the process of breaking up a large quantity of information into smaller pieces and distributing it to multiple computers. Sharding is often used to make the data or computer program more manageable. Shard comes from an Old English word that meant, “to cut” and in present time, a shard is a small piece of a bigger whole. By sharding a massive computer program, you can reduce the computer requirements and make a large program more manageable. In other words, with sharding, smaller portable computers can run what used to require a larger, more powerful, and expensive computer. In blockchain technology, the files are often over 100 gigabytes in size and growing. Using sharding, the huge blockchain program is split up and shared by the network of thousands of computers.
Shill // Shilling
  1. Aggressively advertising an asset for personal financial gain, even to the detriment of others and often while distorting the truth. Also known as pumping.
Sidechains // Side Chain
  1. Blockchains that are interoperable with each other and with Bitcoin, avoiding liquidity shortages, market fluctuations, fragmentation, security breaches and outright fraud associated with alternative cryptocurrencies.
  2. Are blockchains that are interoperable with each other and with Bitcoin, avoiding liquidity shortages, market fluctuations, fragmentation, security breaches and outright fraud associated with alternative crypto-currencies. “Sidechains are new blockchains which are backed by Bitcoins, via Bitcoin contracts, just as dollars and pounds used to be backed by cold hard gold. You could in principle have thousands of sidechains “pegged” to Bitcoin, all with different characteristics and purposes … and all of them taking advantage of the scarcity and resilience guaranteed by the main Bitcoin blockchain, which in turn could iterate to implement experimental sidechain features once they have been tried and tested…”
  3. A side chain is a group of recordings added to the main group, the blockchain, in such a way that data can travel in either direction between both groups of data. A blockchain is a digital recording of data publicly available being maintained simultaneously by a network of computers. A side chain is a separate chain built to upgrade the technology with extra features.
Signature
  1. A value related to a public key which could only have reasonably been created by someone who has the private key that created that public key. Used in Bitcoin to authorize spending satoshis previously sent to a public key.
  2. A cryptographic signature is a mathematical mechanism that allows someone to prove ownership. In the case of Bitcoin, a Bitcoin wallet and its private key(s) are linked by some mathematical magic. When your Bitcoin software signs a transaction with the appropriate private key, the whole network can see that the signature matches the bitcoins being spent. However, there is no way for the world to guess your private key to steal your hard-earned bitcoins.
  3. Signing a message or a transaction consists of encrypting data using a pair of asymmetric keys. asymmetric cryptography allows someone to interchangeably use one key for encrypting and the other key for decrypting. data is encrypted using the private key and can be decrypted by third-party actors using the public key to verify the message was sent by the holder of the private key.
Silk Road
  1. A now defunct marketplace on the Darknet (see above) that was shut down by the FBI. It was best known for selling drugs and other illegal products and accepted Bitcoin.
Simplified Payment Verification (SPV) client
  1. SPV clients are Bitcoin lightweight clients which do not download and store the whole blockchain locally. These wallets provide a way to verify payments without having to download the complete blockchain. An SPV client only downloads the block headers by connecting to a full node.
  2. A method for verifying if particular transactions are included in a block without downloading the entire block. The method is used by some lightweight Bitcoin clients. Synonyms: SPV || Simplified Payment Verification || Lightweight client || Thin client
Smart Contract //Smart Contracts
  1. Also known as a smart property, they are computer protocols that facilitate, verify, or enforce the negotiation or performance of a contract, or that make a contractual clause unnecessary. Smart contracts often mirror the logic of contractual clauses and are being implemented in certain protocol blockchains.
  2. Smart contracts are pieces of code stored on the blockchain that will self-execute once deployed, thus leveraging the trust and security of the blockchain network. they allow users to automate business logic and therefore enhance or completely redesign business processes and service.
  3. When a contract is written in computer code, as opposed to traditional legal language, it is deemed a smart contract. This programmed contract is set up to execute and carry itself out automatically under specified conditions. When a smart contract is on the blockchain, both parties can check its programming before agreeing to it, and then let it do its thing, confident that it cannot be tampered with or changed. It lets two parties agree to complex terms without needing to trust each other, and without needing to involve any third parties. This functionality is the defining feature of the Ethereum blockchain.
  4. Are computer protocols that facilitate, verify, or enforce the negotiation or performance of a contract, or that obviate the need for a contractual clause. Smart contracts usually also have a user interface and often emulate the logic of contractual clauses. Proponents of smart contracts claim that many kinds of contractual clauses may thus be made partially or fully self-executing, self-enforcing, or both. Smart contracts aim to provide security superior to traditional contract law and to reduce other transaction costs associated with contracting
  5. An automated mechanism involving two or more parties where digital assets are put in and redistributed at a later date based on some preset formula and triggering event. The contract can run as programmed without any downtime, censorship, fraud or third party interference.
  6. Contracts whose terms are recorded in a computer language instead of legal language. Smart contracts can be automatically executed by a computing system, such as a suitable distributed ledger system.
  7. Self-running computer code that makes decisions based on pre-set rules that later cannot be changed. The most well-known implementation is the Ethereum system.
  8. Is an algorithm that ensures the commercial contract execution in the blockchain system. It contains information on party’s obligation, confirms the contract terms fulfillment by the parties and automatically determines what to do with the asset – either to transfer the transaction to the participant, return to the sender or something else.
  9. A computer program stored in a blockchain that automatically moves digital assets between accounts if conditions encoded in the program are met. It serves as a way to create a mathematically guaranteed promise between two parties.
  10. Custom software logic that executes automated events when data is written to the blockchain according to rules specified in the contract.
  11. A computer protocol used to digitally facilitate a contract in terms of its verification, negotiation, or performance. A smart contract allows transactions to be carried out and tracked without the use of intermediaries.
    Reference: MIT
  12. Self executing contract with the terms of agreement written into the code
  13. Smart contracts refer to code that is placed on a blockchain and is then executed on it. The code can be audited by the public. Smart contracts are often regarded as a compliment or a replacement to traditional legal contracts. A smart contract might algorithmically implement escrow payments without having the need to create a binding legal contract to hold parties accountable. However, the term is often seen as overly broad as it can mean any block of code placed on the blockchain.
Soft Cap
  1. Generally refers to the minimum amount that an initial coin offering (ICO) needs to raise. If the ICO is unable to raise that amount, it may be cancelled and the collected funds returned to participants.
Soft Fork // Softfork
  1. A softfork is a change to the bitcoin protocol wherein only previously valid blocks/transactions are made invalid. Since old nodes will recognize the new blocks as valid, a softfork is backward-compatible. This kind of fork requires only a majority of the miners upgrading to enforce the new rules.
  2. A change to the rules of a cryptocurrency that creates two separate versions of the blockchain. Soft forks are changes that are backwards compatible with previous rules.
  3. A soft fork is a change made to cryptocurrency technology creating a temporary split in the group of recordings (blockchain). This change creates all new, valid recordings (blocks) that are slightly different from the original blocks. They are just different enough that users of the new technology see blocks from original technology as invalid. But, users of the original technology see no problem with either one. As a result this means, new blocks will work just fine for all computers including those using the original technology. But computers using the original technology will find their blocks are rejected by the rest of the network until they upgrade and rejoin the network. Any new fork in the blockchain can fail and if it does, all users will return to the original recording.
Software wallet
  1. Storage for crypto-currency that exists purely as software files on a computer. Software wallets can be generated for free from a variety of sources. MyEtherWallet (MEW) is one of the popular.
Solidity
  1. Computer programming language that is used to develop smart contracts and decentralized applications on the Ethereum platform and other blockchains.
  2. Solidity is a programming language designed for developing smart contracts. Its syntax is similar to that of JavaScript, and it is intended to compile into bytecode for the Ethereum Virtual Machine (EVM).
  3. Solidity is a contract-oriented programming language for writing smart contracts. It is used for implementing smart contracts on various blockchain platforms.
  4. Solidity is currently the most popular programming language to write smart contracts on the Ethereum blockchain, based around EMCAScript (the basis of JavaScript).
Stable Coin // Stablecoins // Stablecoin
  1. A crypto-currency with extremely low volatility that can be used to trade against the overall market. Tether (USDT) is the only coin that fits this description in the live market that we are aware of at this current time.
  2. Stablecoins are cryptoassets pegged to a certain value or asset — for example, you have stablecoins that trade 1:1 with the US dollar. These are collateralized or not with other cryptoassets.
State Channel
  1. State channels are interactions which get conducted off the blockchain without significantly increasing the risk of any participant. Moving these interactions off of the chain without requiring any additional trust can lead to significant improvements in cost and speed. State channels work by locking part of the blockchain state so that a specific set of participants must completely agree with each other to update it.
  2. A system that moves transaction interactions off the blockchain to reduce cost and increase speed. Transactions are locked until all participants agree and verify them.
Swarm
  1. Swarm is a distributed storage platform and content distribution service, a native base layer service of the Ethereum web three stack. The primary objective of Swarm is to provide a decentralized and redundant store of Ethereum’s public record, in particular, to store and distribute dApp code and data as well as blockchain data
Sybil Attack
  1. Sybil attacks are another security vulnerability specific to peer-to-peer decentralized networks which are open and therefore allow anonymous entrants. The attack is named after the subject of the book Sybil, which deals with the case study of a woman diagnosed with Dissociative Identity Disorder. The main component of the Sybil attack comprises of creating a large number of pseudonymous identities. Once the identities are accepted as peers they try to gain control of the network and subvert the network from within. The network’s resilience depends on how easy it is to create an identity and be accepted as a peer. As there is no 100% failproof firewall against these types of attacks, the best defense against Sybil attacks is to make it as impractical as possible.
  2. If an attacker attempts to fill the network with clients that they control, you would then be very likely to connect only to attacker nodes. Although Bitcoin never uses a count of nodes for anything, completely isolating a node from the honest network can be helpful in the execution of other attacks. This state can be exploited in (at least) the following ways: the attacker can refuse to relay blocks and transactions from everyone, effectively disconnecting you from the network the attacker can relay only blocks that they create, effectively putting you on a separate network and then also leaving you open to double-spending attacks if you rely on transactions with 0 confirmations, the attacker can just filter out certain transactions to execute double-spending attacks low-latency encryption/anonymization of Bitcoin's transmissions (with Tor, JAP, etc.) can be defeated relatively easily with a timing attack if you're connected to several of the attacker's nodes and the attacker is watching your transmissions at your ISP Bitcoin makes these attacks more difficult by only making an outbound connection to one IP address per /16 (x.y.0.0). Incoming connections are unlimited and unregulated, but this is generally only a problem in the anonymity case where you're probably already unable to accept incoming connections. Looking for suspiciously-low network hash-rates may help prevent the second one.
  3. A Sybil attack is an attack where a single adversary is controlling multiple nodes on a network. It is unknown to the network that the nodes are controlled by the same adversarial entity. For example, an adversary can spawn up multiple computers, virtual machines, and IP addresses. They can create multiple accounts with different usernames and e-mail addresses and pretend that they all exist in different countries. Avoiding Sybil attacks is a difficult problem. In centralized systems they are typically avoided through heuristics that do not provide cryptographic assurance of Sybil resilience. For example, a centralized entity may try to avoid Sybil attacks by requiring that an individual IP cannot create more than a specific number of user accounts in a given time interval. Sybil attacks are avoided in Bitcoin by requiring block generation ability to be proportional to computational power available through the proof-of-work mechanism. That way, an adversary is limited in how many blocks they can produce. This provides strong cryptographic guarantees of Sybil resilience.
T
TA
  1. Trend Analysis or Technical Analysis. Refers to the process of examining current charts in order to predict which way the market will move next.
Taker // Market Taker
  1. The "taker" is someone who decides to place an order that is instantly matched with an existing order on the order book.
Tangle
  1. Tangle protocol is one by which a user has their transaction confirmed by the network if and when they help confirm two other user transactions that came before theirs. It is therefore different from the other protocols in that no single node helps maintain the entire ledger at any given time. Each node helps add or edit two transactions at a time. It also differs with other protocols in that miners receive no reward for helping confirm transactions on the ledger unless their own transaction is confirmed on the ledger. The first blockchain to use this protocol is IOTA. They seek to solve the problem other blockchains face when facilitating micropayments, which can incur fees that at times exceed their value.
Target Threshold
  1. The target is the threshold below which a block header hash must be in order for the block to valid, and nBits is the encoded form of the target threshold as it appears in the block header. Synonyms: nBits || Target Not To Be Confused With: Difficulty (a number measuring the difficulty of finding a header hash relative to the difficulty of finding a header hash with the easiest target)
Tendermint
  1. Tendermint is a low-level protocol comprised of two main pieces: a blockchain consensus engine and a generic application interface. Tendermint Core, the blockchain consensus engine, facilitates the peer-to-peer network and provides a proof-of-stake (PoS) consensus. The Application BlockChain Interface (ABCI), on the other hand, acts as a tool for blockchains to link onto the Tendermint Core protocol. The purpose of Tendermint is to be a blockchain engine. It’s meant to be a tool that developers can use to skip the nasty and technical cryptography and jump into the higher level blockchain and application development. Conclusion Tendermint Core and ABCI together make up Tendermint – an open-source blockchain engine for developers of any programming language to build onto. Tendermint shifts developers focus away from the low-level cryptography and onto the application layer. An analogy of what Tendermint is to blockchain would be to compare it to an artist’s canvas. You can express an endless number of ideas on canvas, yet a modern artist rarely needs to think about building and developing their own. Tendermint, like a canvas, is the foundation on which you can invent endless blockchain applications.
Testnet
  1. A second blockchain used by developers for testing new versions of client software without putting a real value at risk.
  2. A global testing environment in which developers can obtain and spend satoshis that have no real-world value on a network that is very similar to the Bitcoin mainnet. Synonyms: Testnet Not To Be Confused With: Regtest (a local testing environment where developers can control block generation)
  3. A global environment built for developers to test platforms. Virtual currencies can be obtained, which have no actual value, for the purposes of troubleshooting or developing new applications, platforms, and ideas.
  4. A secondary blockchain that can be used by developers to test software and updates without risking the current assets on the main blockchain.
  5. An alternative blockchain that is not public and live. It is used to test new code and doesn't transact any real money or value. Allows developers to experiment and learn.
The DAO
  1. The DAO (yes, there’s a difference) was a venture capital fund built on Ethereum. The DAO had an objective to provide a new decentralized business model for organizing both commercial and non-profit enterprises.In 2016, a vulnerability in the DAO code was exploited to siphon off ⅓ of the DAO’s funds to a subsidiary account. This caused a soft and hard fork. It was kinda a big deal.
Thin Client
  1. A method for verifying if particular transactions are included in a block without downloading the entire block. The method is used by some lightweight Bitcoin clients. Synonyms: SPV || Simplified Payment Verification || Lightweight client || Thin client
Ticker
  1. The trading "symbol" or shortened name (typically in capital letters) that refer to a coin on a trading platform. For example: BTC is Bitcoin.
Token(s)
  1. A token is a programmable digital asset with its own codebase that resides on an already existing block chain. Tokens are used to help facilitate the creation of decentralized applications. Synonyms: Token Not To Be Confused With: Bitcoins
  2. Tokens are a digital identity for something that can be owned, created as smart contracts with complex permission systems and interaction paths. Smart contracts can be understood as software agents, which can act autonomously within a scope of a given network according to predefined rule sets. If the governance rules around issuance and management of a token are sufficiently complex regarding how they coordinate a group of stakeholders, token smart contracts may be understood as organizations sui generis.
  3. The means of exchange to give value to a transaction; typically a native cryptocurrency. Some non-currency blockchain architectures can be tokenless
  4. Is a digital asset that is issued for the purpose of attracting investment into a cryptocurrency project or a company. It is close to a stock or a bond by its properties. They are produced during ICO.
  5. Representation of a digital asset built on an existing blockchain
  6. In the context of Blockchains, a token is a digital identity for something that can be owned. Historically, tokens started as meta information encoded in simple Bitcoin transactions, thereby taking advantage of the Bitcoin blockchain’s strong immutability. At a protocol layer, tokens were outsourced extensions to Bitcoin’s core protocol. Instead of being integrated as a feature on a software level, those tokens were created by misappropriating data fields in Bitcoin transactions (such as encoding data in the amount or op_return field). Today, modern tokens are created as sophisticated smart contract systems with complex permission systems and interaction paths attached. Smart contracts can be understood as software agents, which act deterministically and autonomously, within the scope of a given network, according to a predefined rule set. If the governance rules around issuance and management of a token are sufficiently complex regarding how they coordinate a group of stakeholders, token smart contracts may be understood as organizations sui generis. The management rules may reflect those of known legal, organizational entities such as stock corporations, but they do not have to
  7. A unit of value for a blockchain system. Tokens can be used for payment, access, voting, and facilitating the overall blockchain infrastructure. Most tokens are based on Ethereum.
  8. Digital identity for something that can be owned.
  9. Refers to the ‘currency’ of projects built on top of another blockchain, such as Ethereum or Waves. They have raised money via issuing their own tokens or having an ICO. Tokens often represent some utility, resource, or asset value, and are often used in dApps. ERC20 Tokens are the most frequently heard of ‘tokens,’ and are specific to tokens following a protocol on the Ethereum network. Some common tokens include Golem (GNT), Augur (REP), Basic Attention Token (BAT), Iconomi (ICN), etc. (Read about some ERC20 Tokens here.)
  10. Crypto tokens enable the creation of open, decentralized networks, and provides a way to incentivize participants in the network (with both network growth and token appreciation). This innovation, made popular with the introduction of Ethereum, has given rise to a wave of token networks (e.g. prediction markets, content creation networks, etc.) and token pre-sales, or ICOs.
  11. Tokens are a type of digital asset that can be tracked or transferred on a blockchain. tokens are often used as a digital representation of assets like commodities, stocks and even physical products. tokens are also used to incentivise actors in maintaining and securing blockchain networks.
Tokenisation
  1. Representing real-world assets via the use of representative tokens in a blockchain system; in theory, whoever owns the token, owns the asset.
Tokenless Ledger
  1. A distributed ledger that doesn’t require a native currency to operate.
  2. Refers to a distributed blockchain ledger that doesn’t require a token (see above) or other native digital currency to function and to facilitate transactions.
Total Supply
  1. The total number of coins or tokens that are in existence, including those circulating in the public market and those that are locked or reserved.
Transaction Block
  1. A collection of transactions gathered into a block that can then be hashed and added to the blockchain.
  2. A transaction is the most granular piece of information that can be shared among a blockchain network. they are generated by users and include information such as the value of the transfer, the address of the receiver and data payload. before sending a transaction to the network a user signs its contents by using a cryptographic private key. By controlling the validity of signatures, nodes can figure out who is the sender of a transaction and ensure that transaction content has not been manipulated while being transmitted over the network.
Transaction Fee
  1. May be included with any transfer of bitcoins from one address to another. At the moment, many transactions are typically processed in a way where no fee is expected at all, but for transactions which draw coins from many bitcoin addresses and therefore have a large data size, a small transaction fee is usually expected. The transaction fee is processed by and received by the bitcoin miner. When a new bitcoin block is generated with a successful hash, the information for all of the transactions is included with the block, and all transaction fees are collected by that user creating the block, who is free to assign those fees to himself. Transaction fees are voluntary on the part of the person making the bitcoin transaction, as the person attempting to make a transaction can include any fee or none at all in the transaction. On the other hand, nobody mining new bitcoins necessarily needs to accept the transactions and include them in the new block being created. The transaction fee is, therefore, an incentive on the part of the bitcoin user to make sure that a particular transaction will get included in the next block which is generated. It is envisioned that over time the cumulative effect of collecting transaction fees will allow somebody creating new blocks to “earn” more bitcoins that will be mined from new bitcoins created by the new block itself. This is also an incentive to keep trying to create new blocks even if the value of the newly created block from the mining activity is zero in the far future.
  2. A small fee imposed on some transactions sent across the Bitcoin network. The transaction fee is awarded to the miner that successfully hashes the block containing the relevant transaction.
  3. The amount remaining when the value of all outputs in a transaction is subtracted from all inputs in a transaction; the fee is paid to the miner who includes that transaction in a block. Synonyms: Transaction fee || Miners fee Not To Be Confused With: Minimum relay fee (the lowest fee a transaction must pay to be accepted into the memory pool and relayed by Bitcoin Core nodes)
  4. Payment made to the volunteers who process transactions on a blockchain (miners). Transaction fees can vary by cryptocurrency and also by the desired transaction speed.
  5. All cryptocurrency transactions involve a small transaction fee. These fees add up to account for the block reward that miners receive when they successfully process a block. Many transactions are typically processed in a way where there is no fee, but for transactions which draw coins from many bitcoin addresses (and have a large data size), a small transaction fee is usually expected. When a new block is generated with a successful hash, the information for all of the transactions is included with the block, and all transaction fees are collected by that user creating the block. Transaction fees are voluntary on the part of the person making the bitcoin transaction, as the person attempting to make a transaction can include any fee or none at all in the transaction. On the other hand, nobody mining new bitcoins necessarily needs to accept the transactions and include them in the new block being created. The transaction fee is, therefore, an incentive on the part of the bitcoin user to make sure that a particular transaction will get included in the next block which is generated. It is envisioned that over time the cumulative effect of collecting transaction fees will allow somebody creating new blocks to “earn” more bitcoins that will be mined from new bitcoins created by the new block itself. This is also an incentive to keep trying to create new blocks even if the value of the newly created block from the mining activity is zero.
  6. Usually very small fees given to the miners involved in successfully approving a transaction on the blockchain. This fee can vary depending on the difficulty involved in a transaction and overall network capabilities at that moment in time. If an exchange is involved in facilitating that transaction, they too could take a cut of the overall transaction fee.
Transaction ID (TXID) // txid
  1. Is an abbreviation for ‘transaction id’ – this is a hash that is used by both humans and the protocol to reference transactions.
  2. Transaction ID also referred to as a Transaction hash. This is a transaction identifier used to reference transactions on a blockchain. Below is an example from an Ethereum blockchain explorer (https://www.blockchain.com/eth/address/0xb2930b35844a230f00e51431acae96fe543a0347)
Transactions Per second (TPS)
  1. Refers to the amount of transactions that a blockchain is capable of processing each second.
Trezor
  1. A popular hardware cryptocurrency wallet. Trezor was the first Bitcoin hardware but today offers support for altcoins such as Ethereum, Litecoin, Dash, and more.
Truffle
  1. Truffle is a development environment, testing framework and asset pipeline for Ethereum, aiming to make life as an Ethereum developer easier.
Trustless
  1. Blockchains are trustless because no participant needs to trust any other participant for transactions to work out. Trust comes from the system itself, which is impartial.
  2. Trustless is defined as a positive quality where one party is not required to trust another with whom they are conducting a transaction. A trustless system or technology is so secure and smooth in handling your business, that both people can safely hand over money and other valuables without the risk of being cheated.
Turing Complete
  1. The ability of a computing machine to perform a system of data-manipulation rules (such as a programming language, or instruction set). All modern computers are Turing-complete. An example of this is the Ethereum Virtual Machine (EVM) which can process any “computable function”.
  2. Turing complete refers to the ability of a machine to perform calculations that any other programmable computer is capable of. An example of this is the Ethereum Virtual Machine (EVM).
  3. A machine is Turing complete if it can perform any calculation that any other programmable computer is capable of. All modern computers are Turing-complete in this sense. The Ethereum Virtual Machine (EVM) which runs on the Ethereum blockchain is Turing complete. Thus it can process any “computable function”. It is, in short, able to do what you could do with any conventional computer and programming language.
  4. A computer system or computer language is Turing complete (computationally universal), if it can process any code that a general-purpose computer could. Example: Ethereum
tx
  1. Wherever it is used in the text – is an abbreviation for ‘Bitcoin transaction‘
U
Umlinkability
  1. Given a transaction, all senders (included in the ring signature) are equiprobable. This notion is important in the context of Monero’s blockchain.
Uncle
  1. Ethereum blocks that are mined a little late and don’t form part of the main blockchain however can be referenced by later blocks.
Uncle Referencing Reward
  1. A miner who references an uncle also gets about 0.15 ETH per uncle (maximum 2 uncles).
Uncle Reward
  1. If uncles are referenced as uncles by a later block, they create about 4.375 ETH for the miner of the uncle (7/8th of the full 5 ETH reward). This is called the uncle reward.
Unconfirmed Transaction
  1. A score indicating the number of blocks on the best block chain that would need to be modified to remove or modify a particular transaction. A confirmed transaction has a confirmation score of one or higher. Synonyms: Confirmation score || Confirmations || Confirmed transaction || Unconfirmed transaction
  2. When a transaction is proposed, it is unconfirmed until the network has examined the blockchain to ensure that there are no other transactions pending involving that same coin. In the Unconfirmed state, the transaction has not been appended to the blockchain.
Unpermissioned Ledgers
  1. Unpermissioned ledgers such as Bitcoin have no single owner — indeed, they cannot be owned. The purpose of an unpermissioned ledger is to allow anyone to contribute data to the ledger and for everyone in possession of the ledger to have identical copies. True decentralization at its finest!
  2. Such as Bitcoin have no single owner — indeed, they cannot be owned. The purpose of an unpermissioned ledger is to allow anyone to contribute data to the ledger and for everyone in possession of the ledger to have identical copies.
  3. A ledger (see above) that doesn't require the approval of a central authority to be used. It is not owned by anyone and open to participation. A good example is Bitcoin itself.
Unspent Transaction Output (UTXO)
  1. An Unspent Transaction Output (UTXO) that can be spent as an input in a new transaction. Synonyms: UTXO Not To Be Confused With: Output (any output, whether spent or not. Outputs are a superset of UTXOs)
  2. This refers to the amount of cryptocurrency sent to an entity, but not sent on elsewhere. These amounts are considered unspent, and is the data stored in the blockchain.
Untraceability
  1. Given two transactions with the receivers X and Y, it’s impossible (or at least computationally infeasible) to determine if X = Y.
User Activated Soft Fork (UASF)
  1. A Soft Fork activated by flag day or node enforcement instead of miner signaling. Synonyms: User-activated soft fork || UASF Not To Be Confused With: - Miner Activated Soft Fork (a soft fork activated through miner signaling) - Fork (a regular fork where all nodes follow the same consensus rules, so the fork is resolved once one chain has more proof of work than another) - Hard fork (a permanent divergence in the block chain caused by non-upgraded nodes not following new consensus rules) - Soft fork (a temporary divergence in the block chain caused by non-upgraded nodes not following new consensus rules) - Software fork (when one or more developers permanently develops a codebase separately from other developers) - Git fork (when one or more developers temporarily develops a codebase separately from other developers
Utility Token
  1. A token that grants owners access to Blockchain products or services for specific projects. These tokens are not intended to be investments or to grant equity ownership in a project, though some investors speculate on a potential future price increase. Utility tokens are also known as utility coins, app coins, and user tokens.
  2. Utility token is token that has a utility attached to it. They are used for accessing a product or service(at the current time or in future). Utility tokens are released by startups to raise funds through ICOs. One of the examples of Utility token includes Basic Attention Token(BAT). It is a utility token that works in the Brave browser ecosystem. Utility tokens are not aimed for investment. However, they work just fine in ICOs where an investor buys it in the hope that its value will increase shortly.
V
Validator Nodes
  1. Validator nodes are specific nodes in a network that is responsible for constituting blocks and broadcasting these blocks with the network. to create a valid new block they have to follow the exact rules specifed by the consensus algorithm.
Vanity Address
  1. A cryptocurrency public address (see above) that includes custom letters and numbers that are human-readable. An example would look like 1r4523COINCOIN7u01174234kf.
Vaporware
  1. In the world of cryptocurrencies and ICO’s, this term refers to a token and its software that has been advertised but is not yet available to buy, either because it is only a concept or because it is still being written or designed. This word generally does not carry a very positive connotation to it.
Verification Code
  1. Code sent to a second device to ensure the identity of someone logging in to an account. Used for Two-Factor Authentication
VIPER
  1. A programming language created to be a formal introduction to smart contracts.
Vitalik Buterin
  1. Rusian-Canadian programmer and creator of the decentralized application platform Ethereum. Born 1994, Vitalik also contributed to other open-source projects.
Volatility
  1. The measure of fluctuations in price of a financial instrument over time. High volatility in bitcoin is seen as risky since its shifting value discourages people from spending or accepting it.
  2. Created by the rapid and repeated move of an asset's price in both directions (up and down). Volatility adds uncertainty and risk to a market, but can also present opportunity.
  3. The fluctuation in an asset’s prices is measured by its Volatility. Cryptocurrency prices are notoriously Volatile compared to other assets as dramatic price shifts can happen quickly.
W
Wallet Import Format (WIF)
  1. A data interchange format designed to allow exporting and importing a single private key with a flag indicating whether or not it uses a compressed public key. Synonyms: WIF || Wallet Import Format Not To Be Confused With: Extended private keys (which allow importing a hierarchy of private keys)
Watch-Only Address
  1. An address or pubkey script stored in the wallet without the corresponding private key, allowing the wallet to watch for outputs but not spend them. Synonyms: Watch-only address
Weak Hands
  1. This phrase is used to describe cryptocurrency newbies who, instead of hodling, nervously panic-sell their coins in response to market jitters or negative headlines that would not faze experienced traders.
Web Wallet
  1. A type of cryptocurrency wallet that is online (hot storage). Most cryptocurrency exchange wallets are web wallets. Popular for their convenience but can increase hacking risk.
  2. Unlike a local wallet, a web wallet is web-based and held and controlled on a website hosted by a company, usually an exchange. This means that your private keys are handed over and passed to that company to secure for you, based on trust. This method is not as secure as a local wallet as a company having the custody of many users’ private keys in one place is more susceptible to a hack – the more eggs in one basket analogy. However, newer web wallets now feature cold vaults, multisignature technology (multisig) and offline key generation that makes them much safer. Still, web wallets would be more suitable for the purposes of trading bitcoin, using them to spend online, and for the short- to medium-term storage.
Wei
  1. The smallest fraction of an Ether coin (Ether is the native currency of the Ethereum network). One Ether is made of 1000000000000000000 Wei, making Ether very divisible.
Whale
  1. An investor that holds a very large amount of an asset. For cryptocurrencies, whales are often early buyers of a coin or large, institutional buyers that hold a massive stake.
Whisper
  1. Whisper is a part of the Ethereum P2P protocol suite that allows for messaging between users via the same network that the blockchain runs on. The main task of whisper will be the provision of a communication protocol between dapps.
Whitelist
  1. A list of registered and approved participants that are given exclusive access to contribute to an ICO or a pre-sale.
  2. A list of registered and approved participants that are given exclusive access to contribute to an ICO or a pre-sale before the general public.
Whitepaper
  1. An informational document that generally informs readers on the philosophy, objectives and technology of a project or initiative. Whitepapers are often provided before the launch of a new coin or token.
  2. In regards to crypto-economics and cryptocurrencies, a whitepaper is an informational document that generally informs readers and crypto-investors on the philosophy, objectives and technology of a given project or initiative. Whitepapers are often provided before the launch of a new coin or token.
  3. A formal, scientifically-written description of an idea or project. Whitepapers cover the theory and practical applications of cryptocurrencies, as well as many technical details.
X
X11
  1. The X11 algorithm is a proof-of-work hashing function that was developed by Evan Duffield and implemented into the Darkcoin protocol in 2014, later renamed to DASH. X11 was developed and selected by Duffield as the algorithm of choice because of the inherent resistance that it had at the time to Application-Specific Integrated Circuits, or better known as, ASICs.
  2. X11 is a widely used hashing algorithm created by Dash core developer Evan Duffield. X11’s chained hashing algorithm utilizes a sequence of eleven scientific hashing algorithms for the proof-of-work. This is so that the processing distribution is fair and coins will be distributed in much the same way Bitcoin’s were originally. X11 was intended to make ASICs much more difficult to create, thus giving the currency plenty of time to develop before mining centralization became a threat. This approach was largely successful; as of early 2016, ASICs for X11 now exist and comprise a significant portion of the network hashrate, but have not resulted in the level of centralization present in Bitcoin. X11 is the name of the chained proof-of-work (PoW) algorithm that was introduced in Dash (launched January 2014 as “Xcoin”). It was partially inspired by the chained-hashing approach of Quark, adding further “depth” and complexity by increasing the number of hashes, yet it differs from Quark in that the rounds of hashes are determined a priori instead of having some hashes being randomly picked. The X11 algorithm uses multiple rounds of 11 different hashes (blake, bmw, groestl, jh, keccak, skein, luffa, cubehash, shavite, simd, echo), thus making it one of the safest and more sophisticated cryptographic hashes in use by modern cryptocurrencies. The name X11 is not related to the open source GUI server that provides a graphical interface to Unix/Linux users. Advantages of X11 Increased confidence and safety for currencies The increased complexity and sophistication of the chained algorithm provides enhanced levels of security and less uncertainty for a digital currency, compared to single-hash PoW solutions that are not protected against security risks like SPOF (Single Point Of Failure). For example, a possible but not probable computing breakthrough that “breaks” the SHA256 hash could jeopardize the entire Bitcoin network until the network shifts through a hard fork to another cryptographic hash. In the event of a similar computing breakthrough, a digital currency using the X11 PoW would continue to function securely unless all 11 hashes were broken simultaneously. Even if some of the 11 hashes were to prove unreliable, there would be adequate warning for a currency using X11 to take measures and replace the problematic hashes with other more reliable hashing algorithms. Given the speculative nature of digital currencies and their inherent uncertainties as a new field, the X11 algorithm can provide increased confidence for its users and potential investors that single-hash approaches cannot. Chained hashing solutions, like X11, provide increased safety and longevity for store of wealth purposes, investment diversification and hedging against risks associated with single-hash currencies plagued by SPOF (Single Point Of Failure).
Y
Z
Zcash // ZEC
  1. Is an anonymous cryptocurrency created in 2016, which hides sender and recipient identity, as well as the amount of the transaction.
  2. Zcash is a cryptocurrency that grew out of the Zerocoin project, aimed at improving anonymity for Bitcoin users. The Zerocoin protocol was initially improved and transformed into Zerocash, which thus yielded the Zcash cryptocurrency in 2016.
Zeppelin (or Open Zeppelin)
  1. The community of like-minded Smart Contract developers.
Zero Confirmation Transaction
  1. Cryptocurrency transactions are confirmed at regular intervals. New transactions have zero confirmations, which means they have not been verified yet and are less reliable.
  2. Alternative phrasing for an Unconfirmed transaction.
Zero Knowledge Proof // Zero-Knowledge Proofs
  1. Generally speaking, zero-knowledge proofs aim to prove the statement ‘this transfer of assets is valid’ without revealing anything important about the transfer itself.
  2. In cryptography, a zero knowledge proof enables one party to provide evidence that something happened to another party - all without revealing private details.
  3. Proofs to verify that transactions are valid without revealing any information about these transactions, providing privacy to the transaction while maintaining its legitimacy.
zk-SNARK // Zk-Snarks
  1. A zero-knowledge proof methodology. The abbreviation stands for ‘zero-knowledge Succinct Non-interactive ARgument of Knowledge’. They make use of the basic idea that any computational condition can be represented by an arithmetic circuit, which takes some data as input and gives an answer of ‘true’ or ‘false’ in response.
  2. “Zero-Knowledge Succinct Non-Interactive Argument of Knowledge” - an approach to zero knowledge proofs.
0-9
2FA
  1. Two-factor authentication (2FA) is a procedure that is meant to provide increased security of sensitive information in an age of increasing cybercrime. The security protocol calls for both a password and an additional piece of information, often something that is in the physical possession of the user such as a smartphone or credit card.
34% Attack
  1. A 34% Attack is a type of potential attack on a blockchain using the “Tangle” Consensus method where an individual or organization obtains control over at least 34% of the overall network mining power (hashrate) and then attempts to manipulate the general ledger to approve or disapprove chosen transactions by way of majority approval. See 51% Attack.
51% Attack
  1. A condition in which more than half the computing power of a cryptocurrency network is controlled by a single malicious miner or group of miners. If he controls 51% of the network that makes him the authority on the network, giving him the power to spend the same coins multiple times, issue transactions that conflict with someone else’s or stop someone else’s transaction from being confirmed.
  2. When more than half of the computing power of a cryptocurrency network is controlled by a single entity or group, this entity or group may issue conflicting transactions to harm the network, should they have the malicious intent to do so.
  3. The ability of someone controlling a majority of network hash rate to revise transaction history and prevent new transactions from confirming.
  4. A 51% Attack is a type of potential attack on the Bitcoin network where an individual or organization obtains control over a majority of the overall network mining power (hash rate) and then attempts to manipulate the general ledger to approve or disapprove chosen transactions by way of majority approval.
  5. Cryptocurrency's strength comes from a distributed computer network. If anybody gains control of more than 50% of them, they control the network and can double-spend coins.
  6. A situation in which a majority of miners in the blockchain launch an attack on the rest of the nodes (or users). This kind of attack allows for double spending.
  7. The ability of someone controlling a majority of network hash rate to revise transaction history and prevent new transactions from confirming.
  8. That is a situation where more than half of the cryptocurrency network computational resource is controlled by one system member or a group of people. In theory, such a computational resource power volume allows conducting conflicting transactions or might damage the system.
  9. Also known as a Majority Attack. When one or a group of miners control greater than 50% of the network's mining hashrate or computational power