Bip-39 http://www.mediafire.com/file/uilrjfajg2ami24/pdf-14673-57158.pdf While it takes advantage of BIP32 process you may still import BIP39 seeds into Electrum wallet. Also in addition to BIp32 There is certainly BIP44 version which some wallet use for the generation of seeds. Some wallets can import many seed phrases and some have only a person https://bookmarkspecial.com/story20225232/bip39-javascript-helping-the-others-realize-the-advantages-of-bip39-passphrase-https-x-com-tundra838554