HD-DVD encryption key

Hay guys, I'm not nerd enough; what does that omg wowz encryption key I've been seeing all over the place let you do?  plox hepl ; ;

That's what it is, not what it does. What it does it let you decode the information on HD-DVD disks so you can play the videos on them and copy those videos onto other disks. This is called pirating, although I don't know why record company call it that because that just makes it sound even cooler.