Type CODE to get a random code string. Or you could make your own. To make one it just has to be all letters and numbers, no spaces and five characters long. This feature is available because humans are predictable. Type ENCODE to convert plain text to seemingly random characters. Start by typing in your code string, got using the code command or made-up. Then type plain text. There is no character-wise limitations, but if you type something too long, it will go off the side of the screen. Type DECODE to convert text that has been run past the encode command into plain text. You must use the same code string that was used to encode the text. Just type it in and get your message.
Trivia: 1) This has over 60 million different combinations of code strings! 2) You can decode to encode, only you will have to encode in order to decode it. 3) You can type anything that's not a command, it just won't do anything. 4) This is't a caps-sensitive program. 5) There is an easter-egg that you can only find out about by clicking the 'See inside' button.