A simple encryption and decryption programm
It is similar to the Caesar cipher. It simply takes a character of the latin alphabet and replaces it with the 13th character after it. e.g a -> n , b -> o etc. It does the same for capital letters too. If the character is x,y or z it loops back to a,b,c.
e.g. the quick brown fox jumps over the lazy dog ---> gur dhvpx oebja sbk whzcf bire gur ynml qbt
You can use it as well to decrypt a message, by using it in the same way. For example: gur dhvpx oebja sbk whzcf bire gur ynml qbt ---> the quick brown fox jumps over the lazy dog