Bip39 Checksum. The passphrase is not really chosen through the predefined list of 2048 words – it might be any word or phrase you decide on. BIP39 is actually a style and design implementation that lays out how copyright wallets make the list of words (or "mnemonic codes") that make https://thekiwisocial.com/story4501547/bip39-wallet-https-linktr-ee-bip39-the-basic-principles-of-bip39-mnemonic