BIP39 stands for Bitcoin Advancement Proposal 39. The words are picked from a particular list of 2048 popular English words which may be utilized to the make a binary seed (your private critical). This post explains BIP39, the standard that defines how seed phrases are created, and summarizes how BIP32 https://social4geek.com/story4361802/the-definitive-guide-to-bip39-seed-phrase