Demonstrates a ROT13 library
Rob Brooks-Bilson did most of the work on this. I just did some cleanup and expanded it to similar variations.
ROT13 stands for Rotate 13. It takes every character in a string and moves it down the alphabet 13 places. If it falls off the end it wrap around to the front. It is the quintessential bad encryption algorithm. Why 13 places? It serves as its own decrypter.
ROT5 does a similar change to numbers. For each and every number in a string, add 5. If it goes over, subtract 5 instead.
It is ROT13 + ROT5.
ROT47 does the same operation for all ASCII characters from ! to ~
Don't use this to protect any data that might have any value. All of these are increadibly insecure.