This is based on the copyrighted game "Set," although the appearances are slightly different for ease of programming. The applet is password controlled to protect the makers of Set; the purpose of this page is merely to allow the applet writer, a math prof, to use Set as a mathematical example, and to give a couple tools not available to the player of the original card version of the game.
Actually, Set is a great game: both a lot of fun and a good mental exercise. If you don't own a copy, I suggest you get one.