Glossary
BIP-39
The Bitcoin standard that encodes a wallet's master seed as a memorable phrase of 12 or 24 words drawn from a fixed 2048-word list.
BIP-39 specifies how to derive a deterministic wallet seed from a human-readable mnemonic phrase. The wallet generates entropy (128–256 bits), maps it to words from a curated list of 2048, appends a checksum, and produces a 12- to 24-word phrase.
The phrase plus an optional passphrase feeds into PBKDF2 to produce the 512-bit seed that BIP-32 uses to derive every key. Almost every modern self-custodial wallet (across chains, not just Bitcoin) uses BIP-39 mnemonics as its master backup format.