What is a private key?
The secret number that lets you spend your bitcoin. Whoever knows it controls the coins, so it must never be shared.
Not to be confused with: your public keyPublic keyThe partner of a private key. It lets anyone check a signature without revealing the private key under current computing assumptions., your addressAddressA string of letters and numbers that tells someone where to send you bitcoin, a bit like an account number for one payment., your recovery wordsRecovery words (seed phrase)A list of 12, 15, 18, 21 or 24 words that can restore wallet keys. Anyone who has them can take your bitcoin..
Your wallet signs each payment with your private key. The signature proves you may spend the coins without revealing the key itself.
For many single-signature wallets, one set of recovery wordsRecovery words (seed phrase)A list of 12, 15, 18, 21 or 24 words that can restore wallet keys. Anyone who has them can take your bitcoin. can regenerate its derived keys. Imported keys, multisigMultisig (multi-signature)A wallet whose coins need signatures from several keys, such as 2 of 3, so no single key can spend alone. setups and some account or wallet metadata may need separate backups.