This script prevents people from right-clicking on your page to steal your HTML source codes or images. There are a few weaknesses to this, but it is a good barrier against anyone trying to steal your code.
The HexXOR.js script performs XOR encryption and decryption of text according to a key specified by the user. The encrypted data is output in the form of hexadecimals, making it possible to paste the data within an HTML document without intefering with HTML or JavaSript reserved characters. The script is specifically intended to be used to password-protect HTML file content, though other uses (e.g. email address hiding) are of course also possible.