Atbash Cipher
The Hebrews developed their own cipher which involved 'reverse alphabet single substitution'. They essentially devised this cipher to hide the names of various people and places in the Hebrew Bible. An adaptation of polyalphabetic substitution, the ATBASH cipher involves associating the first letter with the last letter, the second with the second last etc in the Hebrew code. So that would mean representing 'A' by 'T', 'B' by 'Sh' and so on, incidentally which is what gives the cipher its name - ATBASH (ATBSh). If you applied this technique to the English language, 'A' would be replaced by 'Z', 'B' by 'Y' etc.