The Code Book is like geek porn Explanations of the theories behind cryptography are woven together with anecdotes of times when code making or code breaking was integral to historical events Singh strikes an excellent balance with this book The clarity of his writing makes the explanations of the mathematics of cryptography very straightforward without dumbing them down, and the historical connections are always fascinating.Personally, my favorite part was the section devoted to the role cryptography played in World War II The cracking of the Enigma at Bletchley Park was probably one of the greatest moments in nerd history.If you re fascinated by puzzles, curious about history, or you want to know what privacy really means in the 21st century, pick up this book You ll have a hard time putting it down. I recently watched The Imitation Game, which left such a bad taste in my mouth, that I wanted to clean it up with something in a similar subject Having read two of Sighn s other books, I picked this one.I had high expectations and it met them nicely The book tells the story of ciphers and encryption through history from what the Greek and the Romans did, through the Enigma, and finally to RSA The style is very easy and pleasant to read, everything is pretty understandable even if you don t have a math background sometimes to the point of being slightly inaccurate and there are a lot of interesting stories inbetween.This book has a single downside it s so pleasant and easy to read, that you ll be done with it in no time Highly recommended. Coming on 20 years after the book was written, it s still quite awesome despite all our subsequent advances in cryptography.Or rather, I should say, we re still living in the same world already transformed by pretty good encryption The methods for breaking the security still falls in the same category as usual interception Of course, the means of interception has gotten amazingly good and creative as hell, but that isn t the primary scope of this book Rather, it s about an awesome crash course in the history of encryption from the Middle Ages or earlier, say Roman or Greek, all the way forward to mechanical solutions a la Babbage and right into the thrilling good stuff of WW2, including Turing and the awesome Code Talkers The advances since then are almost stunningly fascinating, however, and aside from Zimmerman s courageous advent of PGP, the REST of the story may well be trapped under National Security blankets still Alas What I wouldn t give to get a backstage pass to those goings on Well written, accessible, and rather thorough, this book remains one of the best books on encryption for laypersons Highly recommended. By far the best and the most interesting book on the subject recommended to anyone interested in Cryptography and its history I read it in three days mainly because I couldn t put it down. 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. I haven t had this much gleeful delight in a book in a long time This book is pure fun It s not fast reading necessarily, and requires some active engagement to keep up, but man, it is a blast If you read a lot of spy books as a child, or if you re secretly jealous when there s a cipher to be solved in a TV or movie plot and a character says, Yeah, I can totally crack this if I have a few hours, let me get to work, you re going to love this Singh introduces us to famous historical ciphers and codes, as well as the basic principles underlying code making and code breaking you actually get a fairly solid foundation on understanding how to build and crack most classic ciphers CODES AND CIPHERS Some examples of interesting codes this book unpacks and deconstructs with you Transposition Substitution Superencipherment Caesar shift ciphers The Vigenere square cipher The Great Cipher of Louis XIV The as yet unsolved Beale cypher The ADFGVX cipher The Zimmerman telegraph cipher The one time pad cipher aka a Vigenere cipher where the keyword is a random string of letters, at least as many as are in the text to be enciphered which is inherently un decipherable by cryptanalysis But which of course requires both the message writer and receiver to have a copy of the random key, which makes it vulnerable to discovery Plus it s expensive to constantly create brand new random keys for hundreds of messages a day Navajo code talking All the way on up to quantum cryptography, which in theory at least is an uncrackable cipher CRYPTANALYSIS For me, the real genius comes into play here, in cryptanalysis the deciphering of all those nasty little devils Some memorable moments in cryptanalysis history Al Kindi s method of deciphering by analyzing the message in terms of letter frequency, or looking for unusual letter pairings in English, Q is basically always followed by U so if you find a particular letter that is never followed by anything but another particular letter, that s probably Q and U Bazeries method of deciphering the Great Cipher of Louis XIV by analyzing by syllable frequency rather than letter Charles Babbage who, incidentally, invented the prototype of a computer way back in the 1700s invented a method of deciphering the Vigenere cipher First, you look for repeated sequences of letters words that are repeated, and which happened to have gotten encrypted the same way because they land on a multiple of the number of letters the key has You count the spaces in between those words, and draw up a chart with all the different repeated word sequences and the factors that go into those spaces e.g factors of 20 would include 1, 2, 4, 5, 10, and 20 but you wouldn t use just 1 letter for a keyword, so it can t be that Find the number that s a factor common to ALL of the repeated letter sequences, and you know the number of letters in the key word Then you look at the letters the first letter of the keyword would be used to encrypt and use frequency analysis on that I m not explaining this well, but Singh does, and it s so brilliant it makes your ears wiggle The deciphering of the ancient script known as Linear B by Alice Kober and Michael Ventris MODERN CRYPTOGRAPHY Cryptography can basically be credited with the invention of computers Further, cryptographers are the reason you can send encrypted messages that nobody but the receiver can access, and the reason you can buy things over the Internet without people taking you credit card information I have a BlackBerry, so I feel like I m supposed to be a slick techie who knows what encryption is, but I ve never heard it explained as straightforwardly as this book Alice wants to send Bob a letter and she doesn t want the postal service workers to be able to read it Obviously, she can t just send it in a padlocked iron lock box, because she has no way of securely giving Bob a key So what can she do She puts the letter in the iron box, padlocks it, mails it to him He puts his own padlock on it the box now has two padlocks and sends it back to her Now Alice removes her own padlock and sends the box, locked with Bob s own padlock, back to him He removes his padlock and reads the letter That way, the box is never unlocked, but Alice and Bob don t have to find a way to exchange keys This would be especially problematic if the key has to be different for every message or device, the way it is in technology Then there s the asymmetrical public key encryption system designed by Diffie, where Alice has a public key that allows anyone to encrypt a message to her, but cannot be decrypted by the same key it can only be decrypted by another key, the private key to which only Alice has access So Bob could look up Alice s public key, which is known to everyone, encrypt his message to her, and she can decrypt it In the padlock scenario, this would mean Bob would go to the post office, take an Alice padlock, of which there are many copies, lock the box with his message inside, and mail it to her Only Alice holds the key that can unlock this, so the system is secure CONCLUSIONS This is just such a cool book, an absolute ride I can t imagine anyone who wouldn t have at least a little fun with it It s accessible, it s interesting, it s challenging, and it s an unusual read Not a bad thing to say about this one. I never thought I d love a book about mathematics, or ever see the beauty of mathematics My mother was definitely right when she kept pestering me to work harder on my math and argued that it was EVERYWHERE I had argued back saying I would be fine as long as I could perform the basic calculations Maybe this is what growing up is about That being said, this is a very informative book about the past, present and future of cryptography Singh takes us on a journey from ancient times where simple communications and hence simple codes sufficed, through a series of unfortunate events that resulted in the execution of Mary, Queen of Scots,to a time in the future when quantum cryptography might prevail My favorite part is when he talks about the decipherment of Linear B which led me to another amazing book of the same name , an ancient language discovered in the remains of a palace in Crete Oh, and he also makes the Second World War seem interesting in an entirely differently way Singh has a knack for explaining ideas and theories, which might seem mundane if explained by someone else, in a very interesting manner His use of characters called Alice,Bob and Eve to explain the codes, made it easy for a layperson like me to understand the theory behind them.He even adds a few ciphers for us to decipher at the end I must admit I skipped over those pages, but might return to them at some point in the future.I recommend this book to anyone who is fascinated by ancient history, linguistics, cryptography, quantum physics, OR MATHEMATICS This is a fascinating introduction to the world of cryptography It has opened my eyes to a whole new subject that interests me, and now I have spent many hours attempting to create a machine that can decrypt hidden messages It is a wonderful and gripping tale of the history of cryptography, and presents the entire plot as a battle between the code makers and the code breakers I was never left a little bored at parts as I occasionally am during non fiction books because it is a continuous story that flows throughout the pages It keeps you in suspense over the fate of the queen of Scotland, the behind the scenes intelligence conflict in the midst of World War II, and the secret of the Beale treasure For anyone interested in the matter, it is a must read, and for anyone who think they might enjoy the subject, I highly suggest it.The history contained in this near novel doesn t merely end a long time ago, but extends up to the very present, and discusses the exciting possibilities of cryptography in the future Quantum computers and qubits enter the scene, hopefully presenting the holy grail of code making, letting the code makers win the struggle forever Our modern lives lay on the foundation of the public and private key system, including everything from the internet to checks The only reason you are capable having your own private account in security is that complex math is occurring behind the scenes, multiplying two prime numbers hundreds of digits long so that any computer would take the lifetime of the universe to decode the messages you send If you want to understand our modern age, you should definitely read this book. This is a must read before reading Cryptonomicon Or maybe after, like I did If you at all feel uncomfortable in your knowledge of one time pad cyphers, public private keys, or the importance of really good cryptography for average folks, please read this book It s sadly a bit out of date, but Singh does such a brilliant job of methodically building up the complexity in cyphers though history, that you will inevitably learn a ton. Read for the Reading Without Walls challenge, for a topic you don t know much about And even though I didn t finish it in a week, CHALLENGE COMPLETE.I really enjoyed The Code Book The explanations were well done, and the history lessons amazed me, which is odd because I m not a history fan I learned a lot about codes and ciphers and how they work, and that was the best part of it all I liked the writing, so I think I might pick up another Simon Singh book in the future.