Monkey's Audio is a lossless audio compression codec. Since it is lossless, there is no quality loss from the source audio once it is compressed. It achieves a compression rate of about 40%. The files use the .APE file extension. It's main advantage over lossy compression formats such as MP3 is obvious, the quality of MP3 is not near as good. However, the files are much larger than simple MP3 files which is why MP3 files would be more available online than APE files.