is the most common format for storing audio. Almost any player on any platform can open mp3 files. The audio is compressed with loss of quality, but the loss is negligible for the typical user, and the file size is usually less than that of the original files.
is a standard for storing audio files in Apple operating systems. It was developed in 1988 based on the IFF format and is a lossless format - audio data is stored in an uncompressed form. In essence, AIFF is an analog to WAV for the Apple Macintosh platform.