What is DRM (Digital rights management) and how does it work?

Daiku no Medium OST - drm (Extended) Securing Extended Enterprise - Teamcenter Digital Rights Management (DRM) Nadia Ali - Not Thinking ( Sunrise Extended Mix DRM ) DRM Edited and Extended - Little Dread Man Ethiopians Dominate Dubai Marathon: Gemechu & Hirpa Claim Victory! | DRM News | AD1B Prezioso & Marvin - The Riddle (Extended Mix DRM) HD Goldman Sachs CEO Confirms: 'I'm Here As Long As Needed | DRM News Global | AF1S Gabry Ponte & 2 Brothers - Dreams 2010 ( Extended Mix DRM ) DRM One Word Extended Lady GaGa - Bad Romance (Dan Extended DRM) Fix - DRM Black Video when Recording and Streaming Browser skrillex - right here ( 4POP extended remix DRM ).wmv Lady GaGa - Alejandro ( Dave Aude Extended Mix DRM )