A CUNNING CHRONICLE OF THE 50 CODES THAT ALTERED THE COURSE OF HISTORY AND CHANGED THE WORLD From the bestselling author of Bletchley Park Brainteasers and The Scotland Yard Puzzle Book. There have been secret codes since before the Old Testament, and there were secret codes in the Old Testament too. Almost as soon as writing was invented, so too were the devious means to hide messages and keep them under the wraps of secrecy. In 50 Codes that Changed the World , Sinclair McKay explores these uncrackable codes, secret cyphers and hidden messages from across time to tell a new history of a secret world. From the temples of Ancient Greece to the court of Elizabeth I; from antique manuscripts whose codes might hold prophecies of doom to the modern realm of quantum mechanics, you will see how a few concealed words could help to win wars, spark revolutions and even change the faces of great nations. Here is the complete guide to the hidden world of codebreaking, with opportunities for you to see if you could have cracked some of the trickiest puzzles and lip-chewing codes ever created. ----------------------- Praise for Sinclair McKay's books: 'This book [The Secret Life of Bletchley Park] seems a remarkably faithful account of what we did, why it mattered, and how it all felt at the time by someone who couldn't possibly have been born then. - THE GUARDIAN [Bletchley Park Brainteasers] is outrageously difficult but utterly fascinating.

- THE EXPRESS 'Sinclair McKay's account of this secret war of the airwaves in [Secret Listeners] is as painstakingly researched and fascinating as his bestselling The Secret Life Of Bletchley Park, and an essential companion to it.' - DAILY MAIL.