Bitcoin words, in plain English

When one group controls more than half of all mining power. It could reverse its own recent payments or block some transactions, but it still can't steal your bitcoin or create extra coins.

Like an account number people use to send you bitcoin. Most wallets show a new one each time you receive, for privacy.

A machine that sells bitcoin for cash, usually with high fees. Scammers often send victims to them.

The most widely used software for running a Bitcoin node.

Another program for running a Bitcoin node, with stricter filters on extra data in transactions.

A batch of new transactions added to the blockchain about every 10 minutes.

A website for looking up any transaction, address, or block, like mempool.space.

Bitcoin's public record of every transaction, made of blocks linked one after another.

A small device that keeps your keys offline. Also called a hardware wallet.

Each block added on top of the one holding your payment counts as one confirmation. More confirmations, more final.

The setting that tells a wallet which set of addresses to look for from your seed words.

Every 2,016 blocks (about two weeks), mining gets harder or easier so blocks keep coming about every 10 minutes.

Buying small amounts on a regular schedule instead of trying to time the price.

Digital cash notes backed by bitcoin and issued by a "mint," like Cashu or Fedimint.

A fund that holds bitcoin and trades like a stock. You own shares of the fund, not bitcoin.

A company or app where you buy and sell bitcoin for dollars.

A small payment to miners to put your transaction in a block. Fees rise when lots of people are sending.

A change to Bitcoin's rules. A soft fork keeps old software working; a hard fork can split the chain in two.

The very first Bitcoin block, mined January 3, 2009.

About every four years (every 210,000 blocks), the new bitcoin miners earn per block is cut in half.

A wallet app on your phone or computer. Handy for spending.

Data like an image or text stored in a Bitcoin transaction.

The secrets that unlock your bitcoin. Your wallet holds them, and your seed phrase backs them up.

Looks like an email address and lets people send you sats over Lightning without scanning a code.

A layer on top of Bitcoin for fast, cheap payments that settle in seconds.

A separate network (sidechain) linked to Bitcoin, where bitcoin is held by a group of companies.

The waiting room for transactions that have been sent but aren't in a block yet.

How new blocks get added and new bitcoin is issued. Miners compete with specialized computers, and the winner gets paid.

It takes more than one key to move the bitcoin, like "2-of-3."

A computer running Bitcoin software that checks every transaction against the rules.

A social network no company owns. Your account is a key you control.

If a company holds your bitcoin, you're trusting them to give it back.

A payment recorded directly on the blockchain, as opposed to Lightning.

An optional extra word added to your seed words. Each passphrase opens a completely separate wallet.

The real electricity and hardware miners spend to add blocks, which is what secures the network.

The unknown person or group who created Bitcoin.

Short for satoshis, the smallest piece of bitcoin. One bitcoin is 100 million sats.

12 or 24 words that can restore your bitcoin on any compatible wallet. Whoever has them has your bitcoin.

A 2017 upgrade that lowered fees and made Lightning possible. Its addresses start with "bc1q."

Holding your own keys instead of letting a company hold your bitcoin.

Buying small amounts of bitcoin regularly.

Bitcoin's limit of 21 million coins, ever.

Thieves tamper with something you trust, like a wallet device or update, before it reaches you.

A 2021 upgrade that makes complex transactions cheaper and more private. Its addresses start with "bc1p."

A rule that coins can't be spent until a certain date or block.

Short for "unspent transaction output." Think of each one as a bill in your wallet.

An app or device that holds the keys to your bitcoin and lets you send and receive it.

Satoshi's 2008 paper that described Bitcoin.

A tip in sats sent to a Nostr post over Lightning.