Bip39 To Bip32. From this level ahead the seed may very well be composed on paper or spoken over phone and this opened up new, Actual physical ways of backing up the seed (various paper copies in several locations, durable copies on steel plates with additional security from hearth/flood etcetera.). https://bookmarkforest.com/story18924440/bip39-passphrase-generator-fascination-about-bip-39