The Atbash Cipher
What does it do?
Atbash is a substitution cipher that swaps each letter with one on the other end of the alphabet. A becomes Z, B becomes Y, C becomes X, and so on.
This ancient cipher is named after the first/last, and second/second last letters of the Hebrew alphabet: Aleph-Tav-Beth-Shin. Some scholars believe that the Atbash cipher was used to encode certain names and places in the Bible.