R. F. Churchhouse

Some years back I read a similarly broad overview of the history of cryptography (possibly the Code Book by Simon Singh) in which I was thoroughly taken with the Vigenere cipher and disgusted by Playfair. This was primarily because I can use Vigenere by hand without crib sheets - slowly, but I can - and even crack it; whereas Playfair requires a lot more effort just to use, and cracking is more effort than I can be bothered putting in without significant stakes.

This book got me closer to show more resigning myself to Playfair. It also got me perilously close to kinda sorta understanding what people were thinking when they came up with Enigma, RSA, DES, etc. It goes over the mathematics of them in sufficient detail for mathematically-minded people to follow along; I'm not mathematically-minded in that sense so I didn't bother reading all the appendices, but they were there and isn't that the important thing? show less

The Simple substitution cipher is awsm