In my opinion, this book is practically a must-read for anyone living in our increasingly computing intensive world, not just for aspiring computer scientists. It has both depth and accessibility, starting with something familiar in concept to many people (Morse code), and slowly building more and more ideas toward the final realization of a workable computing machine. Great book.

I suspect that up voting recommendations for Petzold's book became a Pavlovian reflex on me. That is a very well written book.