Not in quite the same class as Singh’s definitive Fermat’s Last Theorem, but still a fascinating survey of the history of code making from the earliest days, through thewartime Enigma machines to the present day complexity of 128 bit encryption.
The great thing about the book is probably not the mathematical complexity of modern codes and ciphers but the very human studies of the use and need to transmit secret messages, from the ancient Greeks writing on a messengers bald head, then waiting for the hair to regrow, through the cipher that doomed Mary Queen of Scots to the race to crack the World War II Enigma machines.
One of Simon Singh’s great strengths is being able to get across complex principles in a way that the everyday reader doesn’t find intimidating. This shines through in The Code Book I don’t know if recent editions have the rather cringe-making ‘cipher challenge’ in the back – we can but hope this has disappeared by now – but this shouldn’t put anyone off.
Whatever your mathematical level or inclination, this book is likely to have something to offer.