<div align="center">Codes, Ciphers and Secret Writing (Test Your Code Breaking Skills) </div>

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Book Description:

Experiment with cryptography — the science of secret writing. Cipher and decipher codes: transposition and polyalphabetical ciphers, famous codes, typewriter and telephone codes, codes that use playing cards, knots, and swizzle sticks...even invisible writing and sending messages through outer space. Hours of intrigue and challenge. 45 diagrams.

Date: 2007-06-13 Rating: 4
Non-Mathematical Intro to Ciphers of Historical Interest

This is a good, well-written book requiring essentially no mathematical background. It&#39;s appropriate for teens and older folks interested ciphers. As another writer has pointed out, it&#39;s not current (this is a Dover reprint of a 1972 Simon & Schuster work), and the very few places where it says a code is still in use, it&#39;s likely not. I don&#39;t view this as a problem.

Ciphers are categorized and historical development is given. Invisible inks and the like are discussed, as are microdots, and SETI, though not by that name. Modern ciphers get no mention whatsoever--thus the non-mathematical nature. The approach doesn&#39;t consider computers to any real extent. Also, certain historical items that could have been covered, like the Enigma, aren&#39;t mentioned.

There are three weaknesses, IMHO, that keep it below 5 stars.
(1) Most of the ciphers presented have a set of possible setups, which can effectively be considered keys. E.g., the Caesar Cipher, using the Roman alphabet, has 25 different possible versions, which can be considered 25 different keys. Gardner makes no attempt to explain the relative complexities of breaking the various ciphers.
(2) The age.
(3) There is no index, but the table of contents is detailed.

I expect to use a few of these ciphers in introductory computing classes (think CS1, CS2) in the near future--the explanations are clear enough for undergrads with no real background and minimal interest.

Date: 2003-05-10 Rating: 3
Still Good

This book is a little out of date and a little too basic. It is for the beginner and is not an advanced text. The best thing that it is short. Because it is so short, it had to be packed densely with information, no wordiness. I&#39;ve never had enough time to read The Codebreakers book, too big. Here I got informed in minimal time and the book is much less expensive -- it&#39;s got a better cost to read ratio and cost to information ratio.

Date: 2002-09-28 Rating: 4
Good basic codes, great for beginners.

This is a great reference of basic codes. Excellent explanations, examples. Don&#39;t expect anything too intense, and you won&#39;t be disappointed.

Date: 1999-07-04 Rating: 3
fun for beginners...

Very well written. This book offers an introduction to "crypto-stuff" such as mono/polyalphabetic substitutions and grille methods. It doesn&#39;t go into much of anything else in huge detail, but it offers many methods including "how to build" your own encoding/decoding tools. If you&#39;re looking for some fun reading, I highly recommend it. If you&#39;re serious about learning though, check out "the code breakers" by kahn.

Date: 1999-02-05 Rating: 4
Very educational, practical introduction to codes & ciphers

This is a fascinating introductory book about codes and ciphers. It is very readable and understandable for young adults and older. Anyone who is interested in codes and ciphers will like, and want to own this book.

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