Bip39 Checksum. What this means is usually that should you set a passphrase if you configure your wallet, and then you put some copyright into your wallet - all is effectively; you see your copyright! But then if you decide to install a 2nd wallet, using just your seed phrase https://tools-directory.com/listings569137/bip39-word-list-https-linktr-ee-bip39-not-known-details-about-bip39-compatible-wallet