A little bit of history and fun with cryptograms, secret codes, ciphers and code breaking.
Cryptograms are essentially secret codes. They were first used for secret wartime communications. One of the oldest versions recorded was a strip of paper wrapped around a stick. This type of cryptogram was used by the Spartan Army over two thousand years ago. The paper was wrapped around the stick or staff, edge-to-edge without overlapping, and the message was written vertically. To be read, the paper strip had to be wrapped around a stick of the exact same diameter as the original one used to create the message, so the letters would line up correctly. The receiver knew what diameter stick to use, of course, while any messages intercepted would take some time to be decoded. Even if the enemy knew to use a stick, he had to find one of the right diameter.