What Is Bip39 Passphrase Some words are shorter than 4 letters, like the word “act”. Other words are lengthier than 4 letters, for instance “summary”. One set of mnemonic can be utilized to generate numerous addresses. This process of creating account was introduced in BIP32 & BIP39 long time ago. https://royalbookmarking.com/story18990677/bip39-passphrase-github-little-known-facts-about-bip39-word-list