Definition: AIFF

(Audio Interchange File Format) A digital audio file format from Apple. When a music CD is inserted into a Mac, its contents appear as AIFF files using the same specifications as CD music tracks (uncompressed, stereo, PCM, 16-bit, 44.1 kHz). However, AIFF is capable of supporting mono and stereo, 8- and 16-bit samples and rates both higher and lower than the standard CD (see CD-DA).

Modeled after the Interchange File Format (IFF) developed by Electronic Arts, Apple's AIFF breaks apart the file into chunks. The Common chunk holds file parameters such as sampling rate, and the Sound Data chunk contains the digital sound. See AIFF-C.

AIFF and AAC Files

These examples from the Mac show the contents of the CD in uncompressed AIFF format, very close in size to the disc's CD-DA music tracks. The column on the right shows the file sizes after the music was ripped to AAC, Apple's compressed format at a recording rate of 128 Kbps.