When purchasing or renting video from the iTunes store, you'll get M4V files. M4V can work with DRM copyright protection, which makes sure DRM-protected M4V files could only be played with licensed accounts or specified devices and applications. M4V uses H264 for video coding and AAC for audio coding. It is a special type of MP4 format using file extension. M4V is a video format created by Apple for network streaming and handheld devices like iPod, iPad, iPhone and PSP.