DRM is digital rights management. Many game distributors have used several forms of DRM in a failed attempt to keep their games from being pirated. SecuRom, Tages, SafeDisk and StarForce are just some of them. Most of them do not use it any more, but some will require on-line activation and other forms of DRM. This article explains more.
Somehow I'm not holding my breath for Microsoft to provide any help for this problem.