WHAT IS MP4?
MPEG-4 Part 14
Moving Picture Experts Group
MP4 is a format created in 2001 by an ISO/IEC working group. MP4 files are multimedia files used for storing video/audio and other content. Short for “MPEG-4 Part 14,” this file type is very common and recognized by most systems and devices. Check the list below if you’re not sure how to open MP4 files and which programs can play them.
MPEG-4 Part 14, also known as ISO/IEC 14496-14:2003, is one instance of a more general standard (ISO/IEC 14496-12:2004) with specifications based on Apple’s QuickTime File Format. The MPEG-4 container uses AAC for encoding audio as a means to restrict data copying via lossy compression and playback. Like its many counterparts, the container supports web streaming.
iTunes, QuickTime Player, Windows Media Player, VLC, RealPlayer, etc.