Block and chain, since the word suggests, a sequence made of blocks! So we know very well what are these blocks. Blocks certainly are a kind of database! People who develop computers know databases very well! And for people who do not know, as we say in simple language, then https://www.maanation.com/post/358020_block-and-chain-since-the-word-suggests-a-sequence-made-of-blocks-so-we-determin.html