I made a book for a close friend of mine. It binds together 4 years of knowledge, journeys and secrets. I hid it in another book. It is what is inside that counts; never judge a book by it's cover.

A secret book is one you can hide things in it. It's usually a thick book and adorns an fabric hard cover.

A book has zero access delay. You can flick from one page to another without having to wait. A book also allows you to touch and manipulate words.