Bip39 Mnemonic To Seed. From this position ahead the seed may be penned on paper or spoken about phone and this opened up new, Bodily ways of backing up the seed (several paper copies in various places, durable copies on steel plates with further protection from hearth/flood and so on.). https://finance-credit47036.wikitidings.com/6031932/the_anatomy_of_a_bip39_phrase_entropy_terms_and_security