MP3

Stands for 'MPEG-1 Audio Layer-3.' MP3 is popular compressed audio file format that helped popularize digital music downloads beginning in the late 1990s. MP3 files are typically about one tenth the size of uncompressed WAVE or AIFF files, but maintain nearly the same CD-quality sound. Because of their small size and good fidelity, MP3 files have become a popular way to store music files on both computers and portable devices like the iPod.