Main Page | See live article | Alphabetical index m4a is the abbreviation for MPEG-4 audio. Its protected form is m4p, with digital rights management. If a filename.m4a file is renamed filename.mp4 it should play in any device or program which supports MPEG-4 audio. This article is a stub. You can help Wikipedia by fixing it. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.