DRM: Digital Rights Management. A technology which uses strong crypto to control whether or not a particular computer is permitted to decrypt and play back a particular media file. The idea is that unless a given box has been outfitted with a particular certificate, it doesn't matter if the files are shared or not, only the system for which the certificates were issued could play them back, assuming that the company that provided the certificates didn't decide to revoke them or something.

The 'or something' is the operative part of what screwed one Davis Freeberg not too long ago: An …