Well, I suppose actually it doesn't.  DRM doesn't really taste that good with peanut butter, after all.  But like many people in this modern era, my job depends on the fact that there are provisions in place to prevent copyright infringement.  Specifically something called "Digital Rights Management", DRM vaguely describes a set of actions that someone can do to prevent digital media from being copied.  The most famous negative example of this is Sony's disturbingly stupid release of software that broke peoples Windows computers when they simply inserted an audio CD.