Cryptography Decrypted by H.X. Mel and Doris Baker (ISBN 0-201-61647-5) manages to explain security issues and algorithms in depth in a way that even my 12 year old son understands everything. Simple, plain english – a
pedagogic masterpiece. It is a joy to read which is the best thing about it. Rich in illustrations, full of humor. Although I did not learn anything new regarding cryptography (after going multiple times through the draft of “Handbook of Applied Cryptography” by Menezes et al (if you ever try, bring plenty of Aspirin and Coffee)), I learned that it is possible to explain it in lay terms to lay people. Wow.
Even better: the necessary math explained in the “appendix” is fun to read! Wish I had these chapters when I was in High School suffering from math books as exciting to read as a train time table.
So, if you always wanted to know how PGP or VPN work, – go for it. Costs U$29.95 / CAN$44.95 / AU$ 50, worth every single cent. (No,I am not commercially involved in any way with it, just excited)