A book about computers. Actually, it's about humans. Actually, both.
It's pdf, it's free and it's fucking awesome.
If you've ever wondered what it means to be a human, there is statistically a good chance you won't like the answer this book provides. But if you're really interested in what it means to be a human, you'll read it anyway.
It is a fascinating point of view, and one that could get you farther in figuring it out, or at least help you pull your head out of your ass and see things from a different angle.
tl;dr Read it.