What is an MP4?

Just like how MP3s work by compressing music and audio files without affecting the audio quality, MP4 files are compressed video files. MP4 is also known as MPEG-4 AVC, or advanced video coding. This new technology is going to make video files decrease in size so that they are easier to work with and support. What used to be massive video file of motion and audio are now compressed versions of the same material, called MP4s.