You will discover that this book can be:
A secret message - tear out a page, write a note on it for a stranger, and leave it in a public place.
A recording device - have everyone you contact today write their name in the book.
An instrument - create as many sounds as you can using the book, like flipping the pages fast or slapping the cover.
This Is Not a Book will engage readers by having them define everything a book can be by asking, 'If it's not a book, what is it then?' - with a kaleidoscope of possible answers.