Square (cipher) facts for kids

In cryptography, Square is a special kind of secret code system. It was created by two smart people, Joan Daemen and Vincent Rijmen. They shared their design with the world in 1997.

Square is like an older brother to another very important code system called Rijndael. Rijndael was chosen in 2001 by the U.S. government to be their main way to keep information secret. This system is now known as the Advanced Encryption Standard, or AES for short.

When Square was introduced, a new way to try and break secret codes was also discovered. This method was found by Lars Knudsen and is called the "Square attack".

Square works by changing information in a special way, using eight steps or "rounds." It can handle blocks of information that are 128 bits long, and it uses a secret key that is also 128 bits long.

Square is free for anyone to use because it is not protected by a patent.