Some codes have never been broken. This book looks at the fascinating history of ciphers and cryptography and examines ancient codes, ciphers made by artists, military secret messages, and some codes just made as an intellectual challenge. From the ancient world to the modern digital age, this book is a tour of history's greatest codebreakers and unsolved ciphers.(This book may contain a sharpie mark on the top or bottom edge and may show mild signs of shelfwear.)