During World War II, the United States needed to find a way to protect their messages from their enemies. They devised a code based on the Navajo language. The soldiers who translated the code were known as Code Talkers.

 Code and Cipher Basics By Maggie

Did you know that secret writing began at about the same time that writing became widely used? In fact, the Arabs first invented the science of cryptanalysis in 700 A.D.

Codes and ciphers have been used to send secret messages throughout history. Secret forms of communication are used by businesses to protect their products and information. They are also used by armies and spies to hide coded orders and information from the enemy.

Cryptography, which comes from the Greek word 'cryptos' meaning hidden, is the science of inventing and deciphering codes.  In order to read a coded message, you must have a key.  If you don't have a key to the code, you have to figure it out. One way to figure out the key is to find the most commonly used letter in the code.  Since the most commonly used letter in the English language is 'e,' you can assume that letter is 'e.'  You can then continue to look for other patterns. The science of decoding messages without a key is called cryptanalysis.

Codes and ciphers are not the same thing.  When you write a message in code you replace words, phrases, or messages by different words, letters, or symbols. When you translate the message into code it is called encoding.  Ciphers, on the other hand, translate every single letter, number, or symbol with a different letter, number, or symbol.  When you translate a message using this method it is called enciphering it.

There are lots of interesting ways to communicate secretly. Try creating your own code, and see if your friends can figure out your message. Try to write a story using a cipher. Or make up your own hand signals to us with your friends.

Citations

Books

Hegedus, Alannah, and Kaitlin Rainey.  Bleeps and Blips to Rocket Ships. Toronto: Tundra Books, 2001.

Online Resources

Teitelbaum, Jeremy. "Codes and ciphers." World Book Online Reference Center. 2005. World Book, Inc. 2 Mar. 2005.  <http://www.worldbookonline.com/wb/Article?id=ar121840>.

Images

Copyrighted clip art images from "Microsoft Office Online" <http://office.microsoft.com/clipart/default.aspx?lc=en-us&cag=1> (October-March, 2004-2005). Clip art only available to licensed users for non-commercial purposes.

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