A digital audio comprehsion standard that allows for small files, and near-CD quality sound. It evolved from 1992's MPEG1 (ISO /IEC 11172) standard for audio and video coding. Conservative estimates suggest an MP3 is one-tenth the size of a regular uncompressed audio file, meaning instead of 72 minutes of audio on a CD, there could be just over 12 hours (740 mintues). Because they are easily bootlegged, the Recording Industry Association of America (RIAA) is strying to create a secure format (see SDMI and SCMS ) to prevent piracy.