51% Attack
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.

Cryptocurrency addresses are used to send or receive transactions on the network. An address usually presents itself as a string of alphanumeric characters.

Generally any crypto-currency other than Bitcoin or Ethereum. (Though some Bitcoin folks would probably still say Ethereum is an altcoin)

Taking advantage of a difference in price of the same commodity on two different exchanges. Often mentioned when it comes to comparing ETH prices on Korean exchanges against US exchanges.

Short form for ‘Application Specific Integrated Circuit’. Often compared to GPUs, ASICs are specially made for mining and may offer significant power savings.

Someone still holding an altcoin after a pump and dump crash. Can also just refer to someone holding a coin that is sinking in value with few future prospects.
An expectation that price is going to decrease.

Bitcoin is the first decentralised, open source cryptocurrency that runs on a global peer to peer network, without the need for middlemen and a centralised issuer.

Blocks are packages of data that carry permanently recorded data on the blockchain network.

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.

Block Explorer
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.

Block Height
The number of blocks connected on the blockchain.

Block Reward
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.

Bollinger Band
A margin around the price of a crypto that helps indicate when a coin is overbought or oversold.

An expectation that price is going to increase

Central Ledger
A ledger maintained by a central agency.

cold storage
The process of moving crypto-currency ‘offline’, as a way of safekeeping your crypto-currency from hacking.

The successful act of hashing a transaction and adding it to the blockchain.

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.

Also known as tokens, cryptocurrencies are representations of digital assets.

Cryptographic Hash Function
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.

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.

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.

Distributed Ledger
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.

Distributed Network
A type of network where processing power and data are spread over the nodes rather than having a centralised data centre.

This refers to how easily a data block of transaction information can be mined successfully.

Digital Signature
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.

Double Spending
Double spending occurs when a sum of money is spent more than once.

Ethereum is a blockchain-based decentralised platform for apps that run smart contracts, and is aimed at solving issues associated with censorship, fraud and third party interference.

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.

Government-issued currency, such as the US dollar.

Fear Of Missing Out. The overwhelming sensation that you need to get on the train when the price of something starts to skyrocket.

Forks create an alternate version of the blockchain, leaving two blockchains to run simultaneously on different parts of the network.

Fear, Uncertainty, and Doubt. Baseless negativity spread intentionally by someone that wants the price of something to drop. A FUDster is someone that is spreading FUD.

A measurement of how much processing is required by the ethereum network to process a transaction. Simple transactions, like sending ether to another address, typically do not require much gas. More complex transactions, like deploying a smart contract, require more gas.

Genesis Block
The first or first few blocks of a blockchain.

Going long
A margin trade that profits if the price increases.

Going short
A margin trade that profits if the price decreases.

Hard Fork
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.

The act of performing a hash function on the output data. This is used for confirming coin transactions.

Hash Rate
Measurement of performance for the mining rig is expressed in hashes per second.

Long ago, someone on a bitcoin forum got drunk and made a post with this typo in the place of ‘hold’.

Hybrid PoS/PoW
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).

Limit order / limit buy / limit sell
Orders placed by traders to buy or sell a crypto-currency 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.

Moving Average Convergence Divergence. A trend indicator that shows the relationship between two moving averages of prices.

Margin trading
The act of ‘magnifying’ the intensity of your trades by risking your existing coins. (NOTE: Very risky, only for experienced traders and only on certain exchanges even then)

Market Cap
The total value held in a crypto-currency. It is calculated by multiplying the total supply of coins by the current price of an individual unit.

Market order / market buy / market sell
A simple purchase or sale on an exchange at the current price. Market buys purchase the cheapest ETH available on the order book, and market sells fill the most expensive buy order on the books.

Mining 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.

Mining rig
A computer especially designed for processing proof-of-work blockchains, like Bitcoin. They often consist of multiple high-end graphic processors (GPUs) to maximize their processing power.

Referring to a price going up astronomical levels.

Multi-signature addresses provide an added layer of security by requiring more than one key to authorize a transaction.

A copy of the ledger operated by a participant of the blockchain network.

Oracles work as a bridge between the real world and the blockchain by providing data to the smart contracts.

Peer to Peer
Peer to Peer (P2P) refers to the decentralized interactions between two parties or more in a highly-interconnected network. Participants of a P2P network deal directly with each other through a single mediation point.

Public Address
A public address is the cryptographic hash of a public key. They act as email addresses that can be published anywhere, unlike private keys.

Private Key
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.

Proof of Stake
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.

Proof of Work
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.

Pump And Dump
The recurring cycle of an altcoin getting a ton of attention, leading to a fast price increase, and then of course followed by a huge crash.

Borrowed from online gaming slang, to mean utterly destroyed or ruined

Return on Investment. The percentage of how much money has been made compared to an initial investment. (i.e., 100% ROI means someone doubled their money).

Scrypt is a type of cryptographic algorithm and is used by Litecoin. Compared to SHA256, this is quicker as it does not use up as much processing time.

Sell wall / buy wall
Using a depth chart, traders can see the current limit buy and sell points.

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.

A scaling solution for blockchains. Typically, every node in a blockchain network houses a complete copy of the blockchain. Sharding is a method that allows nodes to have partial copies of the complete blockchain in order to increase overall network performance and consensus speeds.

Smart Contracts
Smart contracts encode business rules in a programmable language onto the blockchain and are enforced by the participants of the network.

Soft Fork
A soft fork differs from a hard fork in that only previously valid transactions are made invalid. Since old nodes recognize the new blocks as valid, a soft fork is essentially backward-compatible. This type of fork requires most miners upgrading in order to enforce, while a hard fork requires all nodes to agree on the new version.

Solidity is Ethereum’s programming language for developing smart contracts.

Stable coin
A crypto-currency with extremely low volatility that can be used to trade against the overall market.

Trend Analysis or Technical Analysis. Refers to the process of examining current charts in order to predict which way the market will move next.

A test blockchain used by developers to prevent expending assets on the main chain.

Transaction Block
A collection of transactions gathered into a block that can then be hashed and added to the blockchain.

Transaction Fee
All cryptocurrency transactions involve a small transaction fee. These transaction fees add up to account for the block reward that a miner receives when he successfully processes a block.

Crypto tokens represent a particular fungible and tradable asset or a utility that is often found on a blockchain.

Turing Complete
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).

A file that houses 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.

Someone that owns absurd amounts of crypto-currency.