Bip39 Checksum. Have an understanding of the risks – forgetting the passphrase suggests losing use of funds: It’s very important to know that forgetting/dropping your passphrase will bring about completely losing use of the related wallet along with the cash it consists of. Mnemonics are illustration of entropy. Starting point https://trackbookmark.com/story20529480/bip39-passphrase-https-linktr-ee-bip39-the-fact-about-bip39-wallets-that-no-one-is-suggesting