code/cryptography/src/rot13_cipher/README.md
ROT-13 is a simple substitution cipher in which each letter is shifted by 13 letters in the alphabet, wrapping around when neccesary. An example is shown below:
Image credit: By Benjamin D. Esham (bdesham) - Based upon ROT13.png by en:User:Matt Crypto. This version created by bdesham in Inkscape.This vector image was created with Inkscape., Public Domain, https://commons.wikimedia.org/w/index.php?curid=2707244
ROT-N, more commonly known as a Caesar cipher, is similar to ROT-13, although letters can be shifted by any number of spaces. This makes ROT-13 a subset of a Caesar cipher where letters are shifted by 13 spaces.