Codes and Ciphers (Collins Need to Know?)

From the history of codemaking to practical examples and tips for cracking your own codes, "Need to Know? - Codes and Ciphers" covers everything you have ever wanted to know about this area in a clear and easy to understand way. Why do we use codes? Why do we need them? From the moment we began communicating, we have looked for ways to make our messages concise and clear; but with the advent of wars and trading, it has been necessary to find ways to keep some of that communication secret. "Need to Know? - Codes and Ciphers" touches on everything from the smoke signals used by the Native Americans to the encryption devices used by government agencies and the military. As well as covering the history of the development of codes and ciphers, this book will also have practical information and advice on how to make codes (whether by pencil and paper, or by computer) and, more importantly, how to break codes! The topics covered are: Native American smoke signals, Masonic signals, flags, and semaphore; Morse code, Braille, ASCII computer language; Letter substitution, both mono-alphabetic and poly-alphabetic; Computer algorithms; The role of codes and ciphers throughout history, for example the American Civil War, the First and Second World Wars; The development of code-breaking devices such as the Enigma machine, which was developed by the Allies during the Second World War to decipher German communications.