Bip39 Checksum. Now, at another degree we use these obtaining and change critical bunch to create individual private keys. Use the above mentioned create non-public keys and chain code and pass them to the above mentioned talked about purpose kchild = kpar + hash(Kpar, cpar, i) to produce personal keys. https://bookmarkfly.com/story18703854/bip-39-https-linktr-ee-bip39-the-fact-about-bip39-wallets-that-no-one-is-suggesting