BIP39 stands for Bitcoin Advancement Proposal 39. The words are chosen from a specific list of 2048 prevalent English words which can be used to the crank out a binary seed (your private critical). Standard recovery phrases use a specific list of 2048 words adhering to the BIP39 standard (Bitcoin https://webcastlist.com/story20343527/a-secret-weapon-for-bip39-words-to-numbers