DRM, or Digital Rights Management, is a misguided attempt by content providers to prevent piracy.

Say I buy an MP3 off the net. I should be able to burn it to a CD or plop it on the MP3 player of my choice. Usually I can. However, if I get a new computer or MP3 player, I have to jump through hoops to transfer the licenses which is a huge pain in the ass.

Bottom line: the content provider gets another revenue stream, the consumer gets screwed, and piracy still exists.