The Free On-line Dictionary of Computing (30 December 2018):

Digital Rights Management

    (DRM) Any technology used to limit the use of
   software, music, movies or other digital data.  This
   generally relies on some interaction between the media and the
   system that plays it.  For example, video DVDs usually
   include a region code.  If this does not match the player's
   region code, the player will refuse to play the disc.

   (2006-02-02)