m4v M4V is a file format developed by Apple for the iTunes store's content and is very similar to the MP4 file extension. M4V is supported exclusively by Apple devices. Other video formats like MP4 and MOV can be converted to M4V in order to run on Apple devices. The most common difference between the M4V and MP4 formats is that M4V offers DRM-Copyright Protection which prevents the copyright of media content. To play a DRM-protected M4V file the computer needs authorization by opening the iTunes account used for buying the media file. However, if the files are not protected by DRM, the user can just rename the file extension from M4V to MP4 in order for it to be recognized by non-apple devices.
aiff The audio interchange file format, and its associated .aif filename extension, is one of the earliest uncompressed audio file formats released for personal computers. The format had its initial release in 1988 and was developed by Apple Inc. using the IFF ' interchange file format, developed by Electronic Arts, as a template. Because the format is inherently lossless, files tend to be large when pitted against lossy audio file formats. Because of this, .aif files are best suited for local storage and playback.