Rot13 is a simple encryption algorithm. It belongs to the Caesar rotations (using an alphabet that has shifted a number of places).
The idea is to move letters thirteen places in the alphabet, and to return to Z to the A. For example, Wikipedia will be Jvxvcrqvn. By using Rot13 again on the text, the original text is retrieved. The same function is therefore useful for both encoding and decoding.
Rot13 can be translated through the following table.
As encryption, Rot13 is not worth it, but Usenet uses it to hide clues, for example. It is also used with some games on the Internet.
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