[castell]

It's the other way around! DRM is a specific form of copy protection. Read the DRM article on Wikipedia: http://en.wikipedia.org/wiki/Digital_rights_management

  "The term [DRM] is also sometimes referred to as copy 
  protection, copy prevention, and copy control, although 
  the correctness of doing so is disputed."

And read http://en.wikipedia.org/wiki/Copy_protection