what is drm

Digital Rights Management (DRM) systems restrict the use of digital files in order to protect the interests of copyright holders.

DRM technologies can control file access (number of views, length of views), altering, sharing, copying, printing, and saving. These technologies may be contained within the operating system, program software, or in the actual hardware of a device.

Some audio files type, as WMA, MP4 (or iTunes M4A) have integrated DRM support, others like MP3, FLAC and Ogg Vorbis do not offer any built support to this technology.