Code: The Hidden Language of Computer Hardware and Software

This is a wonderful book. It claims it wants the reader to understand computers the way computer engineers do. And, if you read carefully, follow the diagrams and think through the explanations,
you will start to. He shows how the main components can be built out of the clever use of a few ordinary bits of technology, all over a hundred years old. I started programming computers about 40 years ago and have a Ph.D in computer science, so I mostly already knew everything in here. But I had the most fun I have had in years reading the first half or so. One of my first programming classes in college involved learning exactly this material. Using little bits of code to simulate relays, switches and such, we built logic gates, then used that code to build 1/2 adders, adders and other components. It was the same sequence of ideas and techniques presented here. We wrote the code in assembler, I think for the PDP-11, or maybe it was in the Mix language used in the Knuth books. This class was my favorite of all my programming classes and reading this book took me back there.
Now I am inspired to do it again, using the circuits described in this book to build a simulation for the web.

So now you think this book is for highly trained engineers and it absolutely isn't. The background you need is you have to understand that switches go on and off, and if you hook a light bulb to a battery, it will light up. The author carefully and fully explains the rest. After getting through this you will know why computers use binary arithmetic, how Braille and Morse code are related, what mathematical logic is. Every day you use that amazing phone or desktop computer to make and play video and music, talk to people anywhere in the world, find out anything you want to know. Read this book and you will know it's not magic, it's the very clever use of a few very simple tools.

This book would be great for a high school student who is interested in science, math or technology and for anybody who wants to know how computers really work, not just what app does what. This was easily my favorite book I read this year.