Audio-only MPEG-4

File extension: .m4a Developed by: International Organization for Standardization Type of format: Media container MIME: video/mp4
MPEG-4 Part 14 or MP4 is a digital multimedia container format most commonly used to store video and audio, but can also be used to store other data such as subtitles and still images. M4A stands for MPEG 4 Audio and is a filename extension used to represent audio files.