.MP3 and .Wav are audio file formats that PowerPoint recognizes. Another very common format is .M4A (audi-only version of an .MP4), and you have heard of even if you do not think so.
.M4A is the format of Apple iTunes music files. It is for the most part a higher quality file than an .mp3 and a smaller files size. Here is what an “M4A” looks like:
Unfortunately PowerPoint does not support the .M4A format, so if you download a song from iTunes it will need to be converted to another format (.mp3 or .wav).
-Troy @ TLC