“The Code Book mixes story-telling with commendably lucid explanations of everything from the cracking of the ‘unbreakable’ Vigenere cipher in the nineteenth century to the modern developments of public-key and quantum cryptography… At a time when cryptography is assuming increasing significance, his book provides a timely and entertaining summary of the subject.”
Economist

“The new book possesses all the qualities of its predecessor. It’s lucidly written, taking just as long as it needs to explain some abstruse problem but not so long as to make one glance wistfully ahead of the page one is reading.”
Evening Standard

“You couldn’t wish for a better guide than Singh. As he demonstrated in his last book, Fermat’s Last Theorem, he has the priceless knack of being able to strip away jargon and describe mathematical processes in something so akin to clear English that even your average non-scientific duffer is able to convince himself that he understands it.”
Mail on Sunday

“Anyone who can navigate the reader through the boggling mathematics of Vigenere’s Square, or the familiar but still seldom understood story of the Enigma, has a special talent as a communicator. Whatever else, this book requires no additional decoding.”
Sunday Herald

“Singh’s power of explaining complex ideas is as dazzling as ever, and as an amusing extra stunt the book contains a cipher challenge…The Code Book will fascinate anyone who, like me, used to treasure their Secret Agent Pen as a child, as well as devotees of spy thrillers, crossword enthusiasts, and paranoiacs of all persuasions.”
Steven Poole, Guardian

“It is hard to imagine a more enthralling book.”
Independent

“Simon Singh, author of Fermat’s Last Theorem has succeeded in The Code Book in making codes and ciphers intelligible to the layman. The heroes of Singh’s absorbing account are code-breakers, ‘linguistic alchemists’, whose obsessive pursuit of cryptography through the ages has transformed the course of history.”
Observer

People love secrets, and ever since the first word was written, humans have written coded messages to each other. In The Code Book, Simon Singh, offers a peek into the world of cryptography and codes, from ancient texts through computer encryption. Singh’s compelling history is woven through with stories of how codes and ciphers have played a vital role in warfare, politics, and royal intrigue… Singh’s accessible style and clear explanations of complex algorithms cut through the arcane mathematical details without oversimplifying.
amazon.com, Therese Littleton

The Code Book contains many fascinating accounts of code-breaking in action, from its use in unmasking the Man in the Iron Mask and the defeat of the Nazis to the breaking of a modern cipher system by a world-wide army of amateurs in 1994. It is especially good on the most recent developments, such as quantum cryptology and the thorny civil liberties issues raised by the advent of very secure cipher systems over the Internet.
amazon.co.uk, Robert Matthews

His exposition is especially effective at putting the reader in the code breaker’s shoes…
The New York Times Book Review

Who can resist a book on secret writing? Simon Singh, author of the bestseller Fermat’s Enigma (a.k.a Fermat’s Last Theorem), now chronicles the classic battle between codemakers and codebreakers. Mr Singh spins tales of cryptic intrigue in every chapter.
The Wall Street Journal

My only regret is that this great book has come far too late. If only someone had given it to me when I was 10, my secret plans for world playground domination might never have been foiled. Bah.
The Observer

This is a book for those like me who enjoy gorging on facts, whether they’re slabs or nuggets.
The Evening Standard

The book is full of fascinating case histories covering the development and practical use of cryptography.
The Mail on Sunday

In Singh’s expert hands, cryptography decodes as an awe-inspiring and mind-expanding story of scientific breakthrough and high drama.
Publisher’s Weekly, US

Singh has created an authoritative, and engrossing read which both explains and humanises the subject… This intelligent, exciting book takes its drive from a simple premise – that nothing is as exciting as a secret.
Scotland on Sunday