The code book How to make it, break it, hack it, crack it

Review by Booklist Review

Gr. 7-12. Based on Singh's excellent adult title The Code Book: The Evolution of Secrecy from Mary, Queen of Scots to Quantum Cryptography (1999), this "Young Readers Edition" doesn't talk down to its audience. In fact, most of the text here appeared in the original book, though some sections, paragraphs, and sentences are omitted and an occasional word is simplified. Trimmed down from the original 402-page volume, this version offers young people a fascinating introduction to the underlying principles, the intriguing history, and the possible future of codes, including the issues and challenges of encrypted Internet communication. Black-and-white illustrations include diagrams and contemporary photographs as well as reproductions of period photos, engravings, documents, and artifacts. A challenging, but fascinating introduction to codes. --Carolyn Phelan

From Booklist, Copyright (c) American Library Association. Used with permission.

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Review by Publisher's Weekly Review

Simon Singh breaks down cryptic messages for the teenage set in The Code Book: How to Make It, Break It, Hack It, Crack It, an adaptation of his bestselling adult title The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptology. He covers actual instances of codebreaking, from its role in the plan to execute Mary, Queen of Scots, to the Navajo code talkers of WWII. (Mar.) (c) Copyright PWxyz, LLC. All rights reserved

(c) Copyright PWxyz, LLC. All rights reserved

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Review by School Library Journal Review

Gr 7 Up-An in-depth look at the use of secret codes throughout history. Singh utilizes an effective narrative style and intersperses fascinating events and people in this abridged version of his adult book of the same title (Doubleday, 1999). The text, illustrations, charts, and tables are the same. A few chapters have been omitted here, yet the overall flow of the book remains smooth. The difference between steganography and cryptography is discussed, as are the two forms of cryptography: transposition and substitution. A detailed history of secret codes is provided, from Herodotus's earliest accounts of secret messages to Arab cryptographers, Mary Queen of Scots, the German Enigma machine, and the Navajo code talkers. Current work on secret codes and their importance in today's society of Internet commerce are discussed. The last chapter, "The Codebreaker's Challenge," consists of four cryptograms. No solutions are given, but the methods to solve them are discussed. Unfortunately, the glossary from the original title is missing in this version. This book will be a popular addition to any YA collection, especially where secret codes and spy books are popular.-Shauna Yusko, King County Library System, Bellevue, WA (c) Copyright 2010. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

(c) Copyright Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

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Review by Horn Book Review

(High School) Abridging detail but not depth from his similarly titled adult book, Singh addresses his sophisticated examination of code making and code breaking to teenagers who are intellectually curious and tenacious and well versed in mathematical principles. Beginning with simple substitution ciphers (one letter or number for another), he explains the thinking behind and the creation of multiple substitution ciphers; cipher machines such as WWII's Enigma; asymmetric ciphers, where the key to the cipher can be held privately and used with a public cipher; and the possible future of quantum cryptography. These explanations are clear and straightforward without a jot of superfluous information. Smoothly integrated with these explanations are sections containing biographical sketches of famous cryptographers; the historical importance of decoded messages; codes in literature; and broken as well as unbreakable language codes, such as the one used by the "Navajo code talkers" during WWII. A discussion of privacy issues surrounding contemporary electronic communication concludes the book. With appendices that extend points from the text, further readings suggested for each chapter, and an index.From HORN BOOK, (c) Copyright 2010. The Horn Book, Inc., a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

(c) Copyright The Horn Book, Inc., a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

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1 The Cipher of Mary Queen of Scots The birth of cryptography, the substitution cipher and the invention of codebreaking by frequency analysis On the morning of Saturday, October 15, 1586, Queen Mary entered the crowded courtroom at Fotheringhay Castle. Years of imprisonment and the onset of rheumatism had taken their toll, yet she remained dignified, composed and indisputably regal. Assisted by her physician, she made her way past the judges, officials and spectators, and approached the throne that stood halfway along the long, narrow chamber. Mary had assumed that the throne was a gesture of respect toward her, but she was mistaken. The throne symbolized the absent Queen Elizabeth, Mary's enemy and prosecutor. Mary was gently guided away from the throne and toward the opposite side of the room, to the defendant's seat, a crimson velvet chair. Mary Queen of Scots was on trial for treason. She had been accused of plotting to assassinate Queen Elizabeth in order to take the English crown for herself. Sir Francis Walsingham, Elizabeth's principal secretary, had already arrested the other conspirators, extracted confessions and executed them. Now he planned to prove that Mary was at the heart of the plot, and was therefore equally to blame and equally deserving of death. Walsingham knew that before he could have Mary executed, he would have to convince Queen Elizabeth of her guilt. Although Elizabeth despised Mary, she had several reasons for being reluctant to see her put to death. First, Mary was a Scottish queen, and many questioned whether an English court had the authority to execute a foreign head of state. Second, executing Mary might establish an awkward precedent--if the state is allowed to kill one queen, then perhaps rebels might have fewer reservations about killing another, namely, Elizabeth. Third, Elizabeth and Mary were cousins, and their blood tie made Elizabeth all the more squeamish about ordering her execution. In short, Elizabeth would sanction Mary's execution only if Walsingham could prove beyond any hint of doubt that she had been part of the assassination plot. The conspirators were a group of young English Catholic noblemen intent on removing Elizabeth, a Protestant, and replacing her with Mary, a fellow Catholic. It was apparent to the court that Mary was a figurehead for the conspirators, but it was not clear that she had given her blessing to the conspiracy. In fact, Mary had authorized the plot. The challenge for Walsingham was to demonstrate a clear link between Mary and the plotters. On the morning of her trial, Mary sat alone in the dock, dressed in sorrowful black velvet. In cases of treason, the accused was forbidden counsel and was not permitted to call witnesses. Mary was not even allowed secretaries to help her prepare her case. However, her plight was not hopeless, because she had been careful to ensure that all her correspondence with the conspirators had been written in cipher. The cipher turned her words into a meaningless series of symbols, and Mary believed that even if Walsingham had captured the letters, he could have no idea of the meaning of the words within them. If their contents were a mystery, then the letters could not be used as evidence against her. However, this all depended on the assumption that her cipher had not been broken. Unfortunately for Mary, Walsingham was not merely principal secretary, but also England's spymaster. He had intercepted Mary's letters to the plotters, and he knew exactly who might be capable of deciphering them. Thomas Phelippes was the nation's foremost expert on breaking codes, and for years he had been deciphering the messages of those who plotted against Queen Elizabeth, thereby providing the evidence needed to condemn them. If he could decipher the incriminating letters between Mary and the conspirators, then her death would be inevitable. On the other hand, if Mary's cipher was strong enough to conceal her secrets, then there was a chance that she might survive. Not for the first time, a life hung on the strength of a cipher. Excerpted from The Code Book for Young People: How to Make It, Break It, Hack It, or Crack It by Simon Singh All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.

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