A
Address
A string of characters, derived from a public key, that identifies where crypto can be sent on a blockchain.
Airdrop
Free tokens distributed to wallet holders, often to promote a new project or reward early users. Be wary of airdrops that ask you to connect your wallet to unknown sites.
All-Time High (ATH)
The highest price an asset has ever reached.
Altcoin
Any cryptocurrency other than Bitcoin.
B
Bear Market
A prolonged period of falling prices and negative sentiment, often defined as a 20%+ drop from recent highs. Learn more.
Bitcoin (BTC)
The first cryptocurrency, launched in 2009, with a fixed maximum supply of 21 million coins.
Block
A batch of transactions added to a blockchain.
Blockchain
A shared, append-only ledger maintained by a network of computers, where each block links to the one before it.
Bridge
A protocol that moves tokens between different blockchains. Bridges have been a frequent target of hacks.
Bull Market
A prolonged period of rising prices and optimism.
C
CEX (Centralized Exchange)
A crypto exchange run by a company that holds customer funds, such as Coinbase or Kraken. Compare exchanges.
Cold Wallet
A wallet that keeps private keys offline, usually a hardware device. Best wallets.
Consensus Mechanism
The method a blockchain uses to agree on valid transactions, such as proof of work or proof of stake.
Custodial Wallet
A wallet where a third party, such as an exchange, controls the private keys on your behalf.
D
DAO
A decentralized autonomous organization, governed by token holders who vote on proposals.
dApp
A decentralized application that runs on a blockchain via smart contracts.
DCA (Dollar-Cost Averaging)
Investing a fixed amount at regular intervals regardless of price. Try our DCA calculator.
DeFi
Decentralized finance: lending, trading and other financial services built on smart contracts. What is DeFi?
DEX (Decentralized Exchange)
An exchange that lets users swap tokens directly from their own wallets via smart contracts.
E
ETF (Exchange-Traded Fund)
A fund traded on a stock exchange. Spot Bitcoin ETFs hold actual bitcoin on behalf of investors.
Ethereum (ETH)
A programmable blockchain that runs smart contracts; ETH is its native currency. What is Ethereum?
F
Fear and Greed Index
A sentiment indicator that summarizes whether the crypto market is driven by fear or greed.
Fiat
Government-issued currency such as the US dollar or euro.
FOMO
Fear of missing out: buying because prices are rising quickly, often at poor prices.
G
Gas Fee
The fee paid to process a transaction or smart contract on networks like Ethereum.
H
Halving
An event roughly every four years that cuts the Bitcoin mining reward in half. How it works.
Hardware Wallet
A physical device that stores private keys offline and signs transactions securely.
Hash Rate
The total computing power securing a proof-of-work blockchain like Bitcoin.
HODL
Crypto slang for holding long term rather than selling, originating from a misspelling of "hold."
Hot Wallet
A wallet connected to the internet, such as a browser extension or mobile app.
I
Impermanent Loss
The value a liquidity provider gives up compared with simply holding the tokens, caused by price changes.
K
KYC
Know Your Customer: identity checks regulated exchanges must perform.
L
Layer 1
A base blockchain such as Bitcoin, Ethereum or Solana.
Layer 2
A network built on top of a layer 1 to make transactions faster and cheaper.
Leverage
Borrowed funds used to increase the size of a trade, amplifying both gains and losses.
Limit Order
An order to buy or sell at a specific price or better.
Liquidation
The forced closing of a leveraged position or loan when collateral falls below a required level.
Liquidity
How easily an asset can be bought or sold without moving its price.
M
Maker Fee
The fee charged when your order adds liquidity to an order book, usually lower than the taker fee.
Market Cap
An asset's price multiplied by its circulating supply.
Market Order
An order to buy or sell immediately at the best available price.
Memecoin
A cryptocurrency driven mainly by internet culture and community hype rather than utility.
Mining
Using computing power to validate transactions and secure a proof-of-work blockchain in exchange for rewards.
N
NFT
A non-fungible token: a unique digital token often used for art, collectibles and in-game items.
Non-Custodial Wallet
A wallet where only you control the private keys.
O
On-Chain Data
Information read directly from a public blockchain. Beginner's guide.
P
Private Key
A secret number that proves ownership of crypto. Anyone with your private key controls your funds.
Proof of Reserves
An audit or attestation showing an exchange holds enough assets to cover customer balances.
Proof of Stake
A consensus mechanism where validators lock up coins to secure the network.
Proof of Work
A consensus mechanism where miners use computing power to secure the network.
Public Key
A cryptographic key derived from your private key, used to generate addresses.
R
Recovery Phrase (Seed Phrase)
A list of 12 to 24 words that can restore a wallet. Never share it or store it online.
Rug Pull
A scam in which project creators abandon a project and take investors' funds. Spot crypto scams.
S
Satoshi
The smallest unit of bitcoin: 0.00000001 BTC.
Self-Custody
Holding your own private keys instead of trusting an exchange.
Slashing
A penalty that destroys part of a validator's stake for misbehavior.
Smart Contract
Code on a blockchain that runs automatically when conditions are met.
Spread
The difference between the buy and sell price of an asset.
Stablecoin
A cryptocurrency designed to hold a stable value, usually $1. What are stablecoins?
Staking
Locking coins to help secure a proof-of-stake network in return for rewards. Staking guide.
T
Taker Fee
The fee charged when your order removes liquidity from an order book, such as a market order.
Token
A digital asset created on an existing blockchain, as opposed to a network's native coin.
Two-Factor Authentication (2FA)
A second verification step at login. Use an authenticator app or security key rather than SMS.
V
Validator
A participant that verifies transactions and proposes blocks on a proof-of-stake blockchain.
Volatility
How much and how quickly an asset's price changes.
W
Whale
An individual or entity holding a very large amount of a cryptocurrency.
Y
Yield
The return earned on crypto, for example from staking or lending.
Keep learning
New to crypto? Start with What is cryptocurrency?, then read how to buy Bitcoin and how to choose a wallet.