Must it be a bound collection of sheets of paper? Can it be a scroll of parchment or papyrus? Can a book be something more ephemeral? Can it be computer code nestling inside an electronic device, waiting to be activated? Is that so very different from board and paper on a shelf waiting to be opened?
I believe the answer to all the questions is no, yes, yes, yes and no!
Let us embrace a broader definition of the term “book” and concentrate of the content not the packaging! After all, apparently, you should never judge a book by it’s cover!