In his first book since the bestselling Fermat's Enigma, Simon Singh offers the first sweeping history of encryption, tracing its evolution and revealing the dramatic effects codes have had on wars, nations, and individual lives. From Mary, Queen of Scots, trapped by her own code, to the Navajo Code Talkers who helped the Allies win World War II, to the incredible (and incredibly simple) logisitical breakthrough that made Internet commerce secure, The Code Book tells the story of the most powerful intellectual weapon ever known: secrecy.

Throughout the text are clear technical and mathematical explanations, and portraits of the remarkable personalities who wrote and broke the world's most difficult codes. Accessible, compelling, and remarkably far-reaching, this book will forever alter your view of history and what drives it.  It will also make you wonder how private that e-mail you just sent really is.
Praise for Fermat's Enigma by Simon Singh:

"Vividly recounted...I strongly recommend this book to anyone wishing to catch a glimpse of what is one of the most important and ill-understood, but oldest, cultural activities of humanity...an excellent and very worthwhile account of one of the most dramatic and moving events of the century."
--Roger Penrose, The New York Times Book Review

"How great a riddle was Fermat's 'last theorem'?  The exploration of space, the splitting of the atom, the discovery of DNA--unthinkable in Fermat's time--all were achieved while his Pythagorean proof still remained elusive...Though [Singh] may not ask us to bring too much algebra to the table, he does expect us to appreciate a good detective story."
--The Boston Sunday Globe

"It is hard to imagine a more informative or gripping account of...this centuries-long drama of ingenious failures, crushed hopes, fatal duels, and suicides."
--The Wall Street Journal

"[Singh] writes with graceful knowledgeability of the esoteric and esthetic appeal of mathematics through the ages, and especially of the mystifying behavior of numbers."
--The New York Times

"[Singh] has done an admirable job with an extremely difficult subject. He has also done mathematics a great service by conveying the passion and drama that have carried Fermat's Last Theorem aloft as the most celebrated mathematics problem of the last four centuries."
--American Mathematical Society

"The amazing achievement of Singh's book is that it actually makes the logic of the modern proof understandable to the nonspecialist...More important, Singh shows why it is significant that this problem should have been solved."
--The Christian Science Monitor