Bitcoin glossary

Address

A string you share to receive bitcoin. Safe to share.

Block

A batch of transactions added to the blockchain, roughly every 10 minutes.

Blockchain

The public ledger of every Bitcoin transaction.

Cold storage

Keeping keys offline, for example on a hardware wallet.

Exchange

A platform to buy and sell. It usually holds your keys.

Fee

What you pay miners to include your transaction. Higher fees confirm faster.

Halving

Every 210,000 blocks, about every four years, the new bitcoin reward for miners halves.

Hardware wallet

A device that stores private keys offline.

HODL

Holding for the long term instead of trading.

Lightning Network

A layer on top of Bitcoin for fast, cheap payments.

Mempool

The waiting room of unconfirmed transactions.

Mining

Computers compete to find a valid new block by making huge numbers of guesses. The winner adds the block and earns the reward. This work is what secures the network.

Not your keys, not your coins

If someone else holds the keys, they control the bitcoin.

Private key

The secret that controls your bitcoin. Never share it.

Sats

Short for satoshis. 100 million sats make one bitcoin.

Seed phrase

12 or 24 words that back up your wallet. Never share them.

Self-custody

Holding your own keys instead of trusting a company.

Whitepaper

The 2008 document by Satoshi Nakamoto that described Bitcoin.