// mime type · audio / video type
video/mp4
MP4 video · .mp4
What video/mp4 is
video/mp4 is the most widely supported video type on the web, typically H.264/AAC. It's the safe default for an HTML <video> source.
How it's used
You'll see this as a Content-Type value on requests and responses — for example Content-Type: video/mp4. It's the type associated with the .mp4 file extension. Audio and video types identify media formats for playback in the browser or a media player.