Address

A Bitcoin address is a short string of letters and numbers that someone gives you to receive bitcoin. Think of it like an email address, but for digital currency. While addresses are related to public keys, they’re not the same—most often, an address is a cryptographic hash of a public key, but in some cases, it can encode other types of scripts.

Bitcoin wallets make it easy to create new addresses whenever you want. It’s common and recommended to use a fresh address for every transaction to help protect your privacy; reusing addresses can make it easier for others to track your activity.

There are different formats for Bitcoin addresses, usually indicated by their prefix and encoding. Legacy addresses, which use Base58 encoding, start with 1 (for P2PKH addresses, representing public key hashes) or 3 (for P2SH addresses, representing script hashes). Newer SegWit addresses use the Bech32 format and start with bc1.

When sending bitcoin, your wallet checks the type of the address you entered and builds an appropriate locking script (called scriptPubKey) so that only the rightful owner of the corresponding private key can spend the received bitcoin later. The scriptPubKey and the amount sent together make up a transaction output.