Pillarpedia - Compendium of Blockchain Terms and Definitions



an electronic resource providing terms and definitions of the Blockchain industry.

  1. Account - an account is an object in a state in a currency system. The account is a record of how much money some particular user has; in more complex systems, accounts can have different functions.

  2. ALTCOIN - “Alternate coin” so it is everything other than Bitcoin (BTC). Bitcoin is the main index for the cryptocurrency market


  3. Arbitrage - The act of buying and selling on different exchanges to earn the difference in the spread. Arbitrage opportunities occur due to differences in exchange reputation, community coin preferences, and ease of bank funding. Take note that fees, limits, and prices could change anytime when you are transferring your coins between exchanges, especially during volatile times.

  4. AshDraked - A situation where you lost all your money.

  5. ASIC - stands for application-specific integrated circuit and refers to hardware specifically designed to optimally perform a single task (such as hashing). ASIC miners (hardware) are therefore specifically designed to perform hashes as fast as possible to increase mining revenue.

  6. ATH - Short form for “All-Time High.” Therefore it means the highest historical price of a specific coin.

  7. Bagholder - A person who buys and hold coins in large quantity hoping to make good profits in the future. The following video refers to the financial markets in the U.S., but the term means the same both industries.

  1. Bear/Bearish - Negative price movement.

  2. BIP - Bitcoin Improvement Proposal or BIP, is a technical design document providing information to the bitcoin community, or describing a new feature for Bitcoin or its processes or environment which affect the Bitcoin protocol. New features, suggestions, and design changes to the protocol should be submitted as a BIP.
    The BIP author is responsible for building consensus within the community and documenting dissenting opinions.

  3. Block - Blocks are found in the Bitcoin blockchain. Blocks connect all transactions. Transactions are combined into single blocks and are verified every ten minutes through mining. Each subsequent block strengthens the verification of the previous blocks, making it impossible to double-spend bitcoin transactions.

  4. Block Height - The block height is just the number of blocks connected in the blockchain. Height 0, for example, refers to the very first block, called the “genesis block.”

  5. Block Reward - When a block is successfully mined on the bitcoin network, there is a block reward that helps incentivize miners to secure the network.
    The block reward is part of a “Coinbase” transaction which may also include transaction fees. The block rewards halves roughly every four years; see also “halving.”

  6. Blockchain - The Bitcoin blockchain is a public record of all Bitcoin transactions. You might also hear the term used as a “public ledger .” The blockchain shows every single record of bitcoin transactions in order, dating back to the very first one.
    The entire blockchain can be downloaded and openly reviewed by anyone, or you can use a block explorer to review the blockchain online.

  7. Borrowing Rate - When you open a leveraged position (Margin Trading), you will be borrowing coins at a pre-determined rate.
    This rate will be added to reflect your position’s overall profit and loss.

  8. BTFD “Buy The Fucking Dip” – When people are running around and selling because of fear, this is the time to buy.

  9. Bull/Bullish - Positive price movement

  10. Buy-Sell Wall - A wall as seen in the depth chart of exchanges is an amalgamation of limit orders of the same price target.

  1. Censorship Fault - a validator failing to accept valid messages from other validators.

  2. Change - Let’s say you are spending $ 1.90 in your local supermarket, and you give the cashier $ 2.00. You will get back 10 cents in change. The same logic applies to bitcoin transactions.
    Bitcoin transactions are made up of inputs and outputs. When you send bitcoins, you can only send them in a whole “output.” The change is then sent back to the sender.

  3. Circulating Supply - The price of a coin has no meaning on its own. However, the price of a coin, when multiplied by the circulating supply, gives the coin’s market cap.

  4. Cold Storage - The term cold storage is a general term for different ways of securing your bitcoins offline (disconnected from the internet).
    Opposite of a hot wallet or hosted wallet, this type of wallet is connected to the web for day-to-day transactions.
    The purpose of using cold storage is to minimize the chances of your bitcoins being stolen from a malicious hacker and is commonly used for more substantial sums of bitcoins.

  5. Cold Wallet - A cold wallet, on the contrary, is an offline wallet.
    It is not connected to the internet, and so its data is irretrievable by any hacker or malicious entity.
    Examples of a cold wallet are a Nano Ledger (USB) or merely a hardcopy wallet (Piece of paper with QR code and private key on it).

  6. Confirmation - A confirmation means that the bitcoin transaction has been verified by the network, through the process known as mining.
    Once a transaction is confirmed, it cannot be reversed or double spent.
    Transactions are included in blocks.

  7. Consensus Algorithm — Proof-of-Authority The Proof-of-Authority algorithm is an alternative form to the PoS algorithm. Instead of staking cryptocurrency (wealth), in PoA, you stake your identity. This means voluntarily disclosing who you are in exchange for the right to validate blocks. Any malicious actions you undertake as a validator will reflect on your identity.
    PoA blockchains require a thorough form of KYC (a verification process that determines you are whom you claim to be).

  8. Contract - an account which contains, and is controlled by EVM code.
    Contracts cannot be controlled by private keys directly; unless built into the EVM code, a contract has no owner once released.

  9. Cryptography - is used in multiple places to provide security for the Bitcoin network. Cryptography, which is essentially mathematical and computer science algorithms used to encrypt and decrypt information, is used in bitcoin addresses, hash functions, and the blockchain.

  10. dApp - stands for decentralized application. This could be any smart contract deployed on the Ethereum blockchain, as they all operate autonomously, aka decentralized. CryptoKitties is an example of a dApp.

  11. Data Availability - the property of a state that any node connected to the network could download any specific part of the state that they wish to.

  12. DDOS - “Short form for ‘Distributed Denial of Service.’
    A well-timed DDoS attack at exchanges during volatile movements may be devastating as traders will not be able to execute any order manually and will be at the mercy of their pre-set, or the lack of, limit orders.”

  13. Decentralized - a decentralized blockchain network is a critical aspect. The network is “decentralized,” meaning that it’s void of a centralized company or entity that governs the network. Bitcoin is a peer-to-peer protocol, where all users within the network work and communicate directly with each other, instead of having their funds handled by a middleman, such as a bank or credit card company.

  14. Difficulty - is directly related to Bitcoin mining (see mining below), and how hard it is to verify blocks in the Bitcoin network. Bitcoin adjusts the mining difficulty of verifying blocks every 2016 blocks. The difficulty is automatically adjusted to keep block verification times at ten minutes.

  15. Digital Signature - a special kind of encryption where there is a process for generating two keys at the same time (typically called a private key and a public key), such that documents encrypted using one key can be decrypted with the other. Generally, as suggested by the name, individuals publish their public keys and keep their private keys to themselves.

  16. Dildo - Long green or red candles

  17. Double Spend - If someone tries to send a bitcoin transaction to two different recipients at the same time, this is double-spending. Once a bitcoin transaction is confirmed, it makes it nearly impossible to spend it double. The more confirmations that a transaction has, the harder it is to double spend the bitcoins.

  18. Dump - To Sell off a coin

  19. Dumping - Downward price movement

  20. DYOR - Do Your Own Research

  21. Economic Finality - a block or state can be considered finalized if it can be shown that if any incompatible block or state is also finalized (e.g., two different blocks at the same height) then there exists evidence that can be used to penalize (the security deposits of) the parties at fault by some amount $X. This value X is called the crypto-economic security margin of the finality mechanism.

  22. EMV Code - Ethereum virtual machine code, 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 can read/write storage, and itself send messages

  23. Encryption - a process by which a document (plaintext) is combined with a shorter string of data, called a key (eg. c85ef7d79691fe79573b1a7064c19c1a9819ebdbd1faaab1a8ec92344438aaf4), to produce an output (ciphertext) which can be “decrypted” back into the original plaintext by someone else who has the key, but which is incomprehensible and computationally infeasible to decrypt for anyone who does not have the key.

  24. Equivocation - a validator sending two messages that contradict each other, or more precisely a validator sending two messages that a validator running the correct algorithm could only send if it sends one message, “rewinds” its internal state to some point before sending that message, then at some future point in time sends the other message. One simple example is a transaction sender sending two transactions with the same nonce.

  25. Ether - the primary internal cryptographic token of the Ethereum network. Ether is used to pay transaction and computation fees for Ethereum transactions.

  26. Externally Owned Account - an account controlled by a private key. Externally owned accounts cannot contain EVM code.

  27. FA - Fundamental Analysis

  28. Fault - an action taken by a validator (or more generally, a participant in a mechanism) that they would not have taken they correctly followed the protocol.

  29. FIB - A Fibonacci retracement is a term used in technical analysis that refers to areas of support or resistance. Fibonacci retracement levels use horizontal lines to indicate where possible support and resistance levels are.

  30. Fill or Kill - A limit order that will not execute unless an opposite order exceeds this limit order’s amount.

  31. FOMO - “Fear of Missing Out,” anxiety leading you to buy a coin based purely on your excitement of market movements.

  32. Fork - a situation where two blocks are generated pointing to the same block as their parent, and some portion of miners see one block first, and some see the other. This may lead to two blockchains growing at the same time. Generally, it is mathematically near-certain that a fork will resolve itself within four blocks as miners on one chain will eventually get lucky, and that chain will grow longer, and all miners switch to it; however, forks may last longer if miners disagree on whether or not a particular block is valid.

  33. Fraud Proof - a set of data usually a part of a block plus some extra “witness data,” (e.g., Merkle branches) that can be used to prove that a given block is invalid.

  34. FUD - “Short form for ‘fear, uncertainty, and doubt.’ Usually used in the form of “xxx spreading FUD again.”
    Example: JPMorgan’s Dimon spread FUD by saying Bitcoin is a fraud that will eventually blow up.”

  35. Full Node - A full node is when you download the entire blockchain using a bitcoin client, and you relay, validate, and secure the data within the blockchain. The data is bitcoin transactions and blocks, which is validated across the entire network of users.

  36. Fungible - Fungible means that a given good is identical. In crypto, we often talk about fungible or non-fungible tokens. A fungible token is Bitcoin. One Bitcoin is and will always be one Bitcoin, just like any other Bitcoin. Some other tokens, however, can be non-fungible, meaning that these tokens can have unique mutual differences.
    An example is Crypto Kitties. The exchange of CryptoKitties is technically achieved by exchanging tokens, but each of the Crypto Kitties tokens is unique, as it needs to reflect a different kitty (for example, hair color). These tokens are non-fungible; they have slightly different properties.

  37. Gas - a measurement roughly equivalent to computational steps. 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. If the total number of gas used by the computation spawned by the transaction, including the original message and any sub-messages that may be triggered, is less than or equal to the gas limit, then the transaction processes. If the total gas exceeds the gas limit, then all changes are reverted, except that the transaction is still valid and the fee can still be collected by the miner. 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.

  38. Genesis block - The genesis block is often referred to as the first block on a blockchain. The genesis block of Bitcoin was created on January 3, 2009; and indicates the birth of the Bitcoin blockchain. Fun fact: the Bitcoin genesis block quotes the headline of the New York Times the day it was created: “03/Jan/2009 Chancellor on the brink of second bailout for banks.”

  39. Halving - Bitcoins have a finite supply, which makes them scarce. The total amount 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.

  40. Hard fork - Usually refers to a chain split, where an upgrade of the network forces miners and nodes to choose between the upgraded network or the original version of the network. Both networks will function separately from here on and will no longer interact with each other. A miner can only put its resources to work on one of the chains, not both (in case of PoW, complex story in case of PoS). A hard fork practically means that the history of the blockchain up until that point has been copied and adjusted by the upgraded network, resulting in two different chains and two different cryptocurrencies. However, cryptocurrency exchanges and wallet applications will need to adjust their software as well to keep supporting the new cryptocurrency. They sometimes choose to develop new software for the upgraded version of the cryptocurrency, but also keep the original software in place, so that the application supports both chains and both coins (Bitcoin and Bitcoin Cash for example). They can also choose to support only one of the versions, putting extra pressure on the community to follow.

  41. Hashrate - The hash rate is how the Bitcoin mining network processing power is measured. For miners to confirm transactions and secure the blockchain, the hardware they use must perform intensive computational operations, which is output in hashes per second.

  42. History – is past transactions listed on the blockchain/ledger that indicates the block the transaction was mined. Note that the state is a deterministic function of history.

  43. HODL - A spin on the investing lingo ‘hold’ — Hold On for Dear Life. A crypto trader who buys a coin and does not see himself selling in the foreseeable future is called a hodler of the coin.

  44. Hot Wallet - is an online wallet. When talking about a hot wallet, we often refer to an exchange wallet that is online because funds need to be quickly available and transferable to users, buyers, and sellers. When a wallet is online, aka connected to the internet, its data is more vulnerable to hackers and malicious entities.

  45. Hyperledger - is an open-source collaborative effort created to advance cross-industry blockchain technologies. It is a platform that unifies companies and developers to coordinate and build blockchain frameworks across various industries. The Hyperledger initiative has over 100 members, including enterprises like IBM, Samsung, Deutsche Borse, American Express, BNP Paribas and Wells Fargo.

  46. ICO - “Short form for “Initial Coin Offering,” which takes a page from the usual IPOs investors know. Coins bought during ICOs are usually sold for a profit when the coin first hits exchanges. This is due to the initial hype, which increases demand for the coin. On the supply side, ICOs create entry barriers as the buyer has to set up his private wallet to receive the coins from the ICO purchase.”

  47. Invalidity Fault - a validator sending a message that a computer running the correct algorithm could not possibly send unless its internal state is manipulated within some way other than rewinding.

  48. JOMO - Joy of Missing Out.

  49. Layer 2 Solutions - are another option for scalability. These are built on top of a secure base-layer blockchain. They can achieve high throughput without compromising security. The second layer of mechanisms can extend the usefulness of public blockchains, letting interactions happen off-chain that still refer back to the reliable base layer when necessary. Applications that need high throughput can use layer 2 environments while still benefiting from a secure base-layer. Examples of Layer 2 scaling solutions are the Lightning Network for Bitcoin, the Loom Network, Raiden, and Plasma Cash for Ethereum.

  50. Leverage - Leverage is a relatively simple concept – instead of putting up the full market value of an asset such as Bitcoin, the trader operates on ‘margin’ – 25:1 leverage (or 25x) means that for every dollar the trader stakes in equity, they can trade $25. This is also known as a 4% margin trade

  51. Light Client - a client that downloads only a small part of the blockchain, allowing users of low-power or low-storage hardware like smartphones and laptops to maintain almost the same guarantee of security by sometimes selectively downloading small parts of the state without needing to spend megabytes of bandwidth and gigabytes of storage on full blockchain validation and maintenance.

  52. Lightning Network - is an extra layer (“layer 2”) on top of a blockchain (on Bitcoin, for example) that enables faster transaction processing by using ‘payment channels.’ A payment channel can be opened between peers (parties) that register all transactions between these parties without sending them all straight to the actual blockchain. As the payment channel closes, all transactions are settled, and the outcome of all transactions is sent to the actual blockchain.

  53. Limit Order - An order placed at a future price that will execute when the price target hits.

  54. Liveness Fault - a validator failing to submit a message that according to the protocol they should have submitted (or submitting a message later than they should have).

  55. Long - A position that a trader takes. To take a long position on something is to believe its value will rise in the future.

  56. Loose Coupling - chains A and B are loosely coupled if (i) any state of A points to some state of B (and vice versa), and (ii) they are not tightly coupled.

  57. Mainnet - a blockchain protocol fully developed and deployed, meaning that cryptocurrency transactions are being broadcasted, verified, and recorded on a distributed ledger technology (blockchain).

  58. Margin Trading - Margin trading with cryptocurrency allows traders to open a position with leverage and trade without putting up the full amount.

  59. MCAP | Market Cap - A stock’s market cap refers to the market value of the company’s outstanding shares.
    The cryptocurrency market, the market cap is used to illustrate a coin’s dominance in the entire cryptocurrency market.

  60. Message - a sort of “virtual transaction” sent by EVM code from one account to another. Note that “transactions” and “messages” in Ethereum are different. A “transaction” in Ethereum parlance refers explicitly to a digitally signed piece of data, originating from a source other than executing EVM code, to be recorded in the blockchain. Every transaction triggers an associated message, but messages can also be sent by EVM code, in which case they are never represented in data anywhere.

  61. Mining - is the process of using computer hardware to do mathematical calculations for the Bitcoin network in order to confirm transactions. Miners collect transaction fees for the transactions they confirm and are awarded bitcoins for each block they verify.

  62. Moon - extreme bullish movement of a coin that it is heading to the Moon.

  63. Multi-signature - is a signature formed by multiple other signatures combined. Some operations or actions on a blockchain may require a multi-signature, meaning multiple users (addresses) are required to sign the operation in order for it to become executed.

  64. Oracles - For smart contracts, oracles are a middleware product in which data outside of the blockchain (such as real-world data from weather to stocks) is connected to it. That data is then used for conditions of smart contracts. Ethereum is self-contained, so oracles would allow smart contracts to branch out into real-world applications by bringing the data to it. An example of this would be sports betting, where a smart contract would be resolved by receiving the scores of a sporting event.

  65. OTC - Over-the-counter or off-exchange trading is done directly between two parties, without the supervision of an exchange. It is contrasted with exchange trading, which occurs via exchanges.

  66. P2P (Peer-to-Peer) - a decentralized network where all participants are directly connected with each other without some sort of central connectivity point. All peers (participants, nodes/miners) are directly connected with one another.

  67. Patricia tree (trie) - a data structure which stores the state of every account. The trie is built by starting from each individual node, then splitting the nodes into groups of up to 16 and hashing each group, then making hashes of hashes and so forth until there is one final “root hash” for the entire trie. The trie has the important properties that (1) there is exactly one possible trie and therefore one possible root hash for each set of data, (2) it is very easy to update, add or remove nodes in the trie and generate the new root hash, (3) there is no way to modify any part of the tree without changing the root hash, so if the root hash is included in a signed document or a valid block the signature or proof of work secures the entire tree, and (4) one can provide just the “branch” of a tree going down to a particular node as cryptographic proof that that node is indeed in the tree with that exact content. Patricia trees are also used to store the internal storage of accounts as well as transactions and ommers.

  68. Permissioned Blockchain - Specific nodes or entities on these blockchains have authorizing powers over others, allowing them to appoint validators and allow or deny access to the network. Permissioned blockchains have centralized authorities, can be closed and private ecosystems, and are often less transparent. Example: Ripple (XRP). These blockchains are often deployed in the area of internal business operations.

  69. Permission-less Blockchains – a blockchain where users don’t need permission from anyone on the network in order to perform certain actions, including joining the network. Therefore, it is publicly available to anyone, usually very transparent and decentralized. The (voting) power is equally distributed between all network participants — example: Bitcoin (BTC), Litecoin (LTC).

  70. Plasma - is the Lightning Network concept implemented on the Ethereum blockchain.

  71. PoC - Proof-of-Concept, another name for a pre-launch release.

  72. Pool - As part of bitcoin mining, mining “pools” are a network of miners that work together to mine a block, then split the block reward among the pool miners. Mining pools are an excellent way for miners to combine their resources to increase the probability of mining a block, and also contribute to the overall health and decentralization of the bitcoin network.

  73. Prepare and Commit - two types of messages that validators can send in many types of consensus protocols

  74. Private Key - is a string of data that shows you have access to bitcoins in a specific wallet. Think of a private key like 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.

  75. Proof of Stake - An algorithm used for the PoS algorithm applies, the miners stake the cryptocurrency to increase their chances of being selected to validate a block. The cryptocurrency ‘put at stake’ is locked up as a deposit to ensure the miner validates the block according to the rules. If the miner violates the rules, then deposit the is ‘burned’ aka destroyed. On the contrary to PoW, PoS has fewer costs involved for the miners (PoW requires a lot of electricity and hardware costs for the hashing process, PoS only requires things like server setup, DDoS protection, et cetera).

  76. Proof of Work – is the hash of a block header (i.e., blocks of bitcoin transactions). A block is considered valid only if its hash is lower than the current target. Each block refers to a previous block adding to earlier proofs of work, which forms a chain of blocks, known as a blockchain. Once a chain is formed, it confirms all previous Bitcoin transactions and secures the network.

  77. Proof of Work Nonce - a meaningless value in a block which can be adjusted to try to satisfy the proof of work condition.

  78. Public Address – is a cryptographic hash of a public key. A public address typically starts with the number “1.” Think of a public address like an email address. It can be published anywhere, and bitcoins can be sent to it, just like an email can be sent to an email address.

  79. Pump - When a coin skyrockets in price without reason or when the company provides insight on the latest developments causing price movement.

  80. Pump and Dump - The recurring cycle of an Altcoin getting a spike in price followed by a massive crash. Such movements are often attributed to low volume, hence the ‘pump.’ Traders who pump, buying huge volumes, may wish to invoke FOMO from the uninformed investors and then dump, or sell, their coins at a higher price.

  81. RBF - Replace By Fee refers to a method that allows a sender to replace a “stuck” or unconfirmed transaction with a new one that uses a higher fee. This is done to make sure a transaction confirms as quickly as possible. The “replacement” transaction uses the same inputs as the original one. This is not considered a double-spend, as the receiving address(es) typically remain the same.

  82. REKT - When you have a terrible loss.

  83. Relayer - is any party or entity which hosts an off-chain order book. They provide a way for users to add, remove, and update this order book through an API, GUI, or both. In doing so, relayers help traders discover counterparties and ferry cryptographically signed orders between them. Once two parties agree on the terms of an order, the order is settled directly on the Ethereum blockchain via the 0x protocol smart contracts.

  84. Reverse Indicator - Someone who is always wrong predicting price movements.

  85. RSI - Relative Strength Index

  86. SAJ Candle - Huge green candle

  87. Satoshi - is the smallest granularity of a given cryptocurrency, aka the smallest decimal entity of a cryptocurrency. An example of Bitcoin, 0.00000001 BTC (8 decimals) is the smallest division of Bitcoin possible, and therefore reflects one Satoshi.

  88. Security Deposit - a quantity of ether that a user deposits into a mechanism (often a proof of stake consensus mechanism, though this can also be used for other applications) that a user expects typically to be able to withdraw and recover eventually, but which can be taken away in the event of malfeasance from the user’s side.

  89. Self-Executing - Functioning by itself, not controlled by any other party other than itself. Self-executing smart contracts would cut costs/overhead by removing the need for an arbitrator and trust towards a third party.

  90. Serialization - the process of converting a data structure into a sequence of bytes. Ethereum internally uses an encoding format called recursive-length prefix encoding (RLP).

  91. Shard - a subset of the state which is managed by different nodes from the nodes that manage other shards. Usually, shards must be tightly coupled, and side chains must be loosely coupled.

  92. Shill - The act of unsolicited endorsing of the coin in public. Traders who bought a coin has an interest in shilling the coin, in hopes of igniting the public’s interest in that particular coin.

  93. Shitcoin - A coin with no potential value or use.

  94. Short - A position that a trader takes. To take a short position on a coin is to believe its value will fall in the future.

  95. Slashing Condition - a condition which, if triggered by a validator, causes the validator’s deposit to be destroyed.

  96. Smart Contract - A computer protocol meant to streamline the process of contracts by digitally enforcing, verifying, or otherwise managing them. Given the nature of the blockchain, all of these transactions are visible and verifiable through the code itself.

  97. Soft Fork - implies an upgrade to the network protocol, just like a hard fork, but it does not force miners and nodes to choose between the old or the new network. Old nodes and miners can still participate in the new network without upgrading. However, if the old network holds the majority of the mining power, it starts to become more complicated. Upgraded nodes are not able to participate in the network of the old nodes, and so if the old nodes create theirs on offshoot from the new network.

pinned #2

  1. Solidity, LLL, Serpent, and Vyper - programming languages for writing contract code which can be compiled into EVM code. Serpent can also be compiled into LLL. Solidity is a C+±like language (and is the most widely used), Serpent and Vyper are Python-like languages (the developer of the two currently recommends Vyper more), and LLL is an acronym for Lisp-like language.

  2. Stale - is a block that is created when there is already another block with the same parent out there; stales typically get discarded and are wasted effort.

  3. Stale Block - is a valid block that was once broadcasted by a miner while another valid block was being broadcasted by another miner simultaneously. Nodes will only register one of these blocks, depending on what block reaches them first. When both blocks have been propagated, some nodes will have block A as their last valid block, whereas some will have block B. Both blocks are valid at this point, but one of them will become invalid as soon as a new block is broadcasted on top of the other. Let’s say a miner finds a new block afterward and has block B registered as the last block before that. It now puts the new block on top of block B and broadcasts this chain to all other nodes. Other nodes, regardless of their last block being block A or B, now recognize that this blockchain record is longer/heavier than the one they currently possess and are forced to follow this blockchain record. This means all nodes that had block A as their latest block, now have to erase block A and replace it with block B and the other new block on top of it. A stale block is a block that was once valid but is no longer included in the truthful (longest/heaviest) chain (in this example, block A has become a stale block).

  4. State - the set of data that a blockchain network strictly needs to keep track of, and that represents data currently relevant to applications on the chain. In a currency, this is simply balances; in more complex applications this could refer to other data structures that the application in question needs to keep track of (e.g., who has a what domain name, what is the status of a given contract, etc.). The post-state of a block in the state after executing all transactions in the ancestors of the block starting from the genesis going up to and including the transactions in that block itself.

  5. Storage - a key/value database contained in each account, where keys and values are both 32-byte strings but can otherwise contain anything.

  6. Swarm - an upcoming P2P data storage protocol optimized for static web hosting.

  7. Swing - Zig zag price movement (Upwards and downwards).

  8. TA - Technical Analysis

  9. Tight Coupling - chains A and B are tightly coupled if (i) any state of A points to some state of B (and vice versa), and (ii) a state of A should not be considered admissible unless both that state itself and the state of B that it points to are valid and data-available.

  10. Token Airdrop - a coin/token is distributed to the community for free or for small tasks. This is done to ensure early distribution and to have as many people with “skin in the game” as possible. An Airdrop aims to build a huge community easily as people will pay attention to the coin they hold. Furthermore, they tend to promote this coin for profits, and this may cost the Development Team little to achieve the goal of advertisement.

  11. Transaction - is when data is sent to and from one bitcoin address to another. Just like financial transactions where you send money from one person to another, in bitcoin you do the same thing by sending data (bitcoins) to each other. Bitcoins have value because it’s based on the properties of mathematics, rather than relying on physical properties (like gold and silver) or trust in central authorities, like fiat currencies.

  12. Trustless - Does not require a third party to verify or manage. Smart contracts are primarily trustless, as they are meant to occur by themselves once the stipulations are met.

  13. Uniquely Attributable Fault - a fault such that there exists clear evidence which can be used to determine exactly which validator committed the fault. For example, liveness faults are not uniquely attributable because if a message from A fails to reach B, it could be because A failed to send that message, or because B failed to listen to it, whereas equivocation faults are uniquely attributable.

  14. Validator - a participant in proof of stake consensus. Validators need to submit a security deposit in order to get included in the validator set.

  15. Validity - the property of a state that it is indeed the result of executing a valid history of transactions

  16. Wallet - Just like with paper dollars you hold in your physical wallet, a bitcoin wallet is a digital wallet where you can store, send, and receive bitcoins securely. There are many varieties of wallets available, whether you’re looking for a web or mobile solution. Ideally, a bitcoin wallet will give you access to your public and private keys. This means that only you have rightful access to spend these bitcoins, whenever you choose to.

  17. Weak Hands - Those who cannot be patient and sell at a loss when the market is down.

  18. Whale - Very wealthy trader/market mover.

  19. Whisper - an upcoming P2P messaging protocol.

  20. Whitepaper - is an in-depth paper on a specific topic that presents a problem and provides a possible solution. New blockchain ideas are often presented in the form of a whitepaper.


DAO or a Decentralized Autonomous Organization - is an [organization] represented by rules encoded as a computer program that is transparent, controlled by shareholders and not influenced by a central government. A DAO’s financial transaction record and program rules are maintained on a [blockchain].
The precise legal status of this type of business organization is unclear.