The M4V file format was developed by Apple. It is very similar to the MP4 file type, with the main difference being that M4V may contain Apple's DRM protection, Fairplay. Video content downloaded from the iTunes store is likely to be in M4V format. If M4V file does have DRM enabled then the iTunes account used to procure the file will need to be authenticated on the computer playing the file.
The M4V file is a container that allows audio and video. In certain circumstances where Apple's DRM has not be applied to the file, it is possible to play the file from a different unauthenticated computer by amending the file extension from .m4v to .mp4. Additionally m4v provides the functionality to create chapter information which is not possible with MP4.
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The MOV file format is most commonly associated with Apple and the QuickTime video clip. The file format was developed by Apple as was QuickTime Player, it is compatible with both the Microsoft and MacOS platforms. MOV files are capable of storing two or more tracks which can be video, audio, text, graphics or effects. This flexibility makes this file format very popular for music and video editing.
MOV files use a proprietary compression algorithm and each track that is held within the file is made up of an encoded media stream or a reference to a media stream that is located in another file - this allows the embedding of existing media. QuickTime player which was developed and created by Apple allows a user to open and play .MOV files and later version of QuickTime Player, such as QuickTime Pro allows the user to edit and export .MOV files.
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