MP3 is actually an MPEG-1 or MPEG-2, layer 3 file. MPEG is an acronym for Moving Picture Experts Group - an international subcommittee that develops standards for digital audio and video compression. MPEG files are smaller than other digital multimedia formats, so they use less disk space while maintaining the quality of the original source. Sample Rates less than 32kHz (16kHz, 22kHz, and 24kHz) produce an MPEG-2 file. Sample Rates 32kHz and above (32kHz, 44kHz, and 48kHZ) produce an MPEG-1 file.