Bip39 Word List Ledger. From this level ahead the seed might be created on paper or spoken above telephone and this opened up new, Bodily means of backing up the seed (many paper copies in numerous areas, durable copies on steel plates with extra safety from fire/flood and many others.). https://johnathanfpzky.buscawiki.com/1111139/the_anatomy_of_a_bip39_phrase_entropy_phrases_and_security