Audio Interchange File Format. A common Macintosh audio file format. It can be mono or stereo, at sampling rates up to 48kHz. AIFF files are QuickTime-compatible and support uncompressed mono, stereo, and multichannel audio at many different resolutions and sampling rates, including the CD standard. It was designed to serve as a universal interchange format that allows any program to open a digital recording created by any other program. AIFF is high-quality audio, used in pro-level Mac and PC audio software. As AIFF is a standard for uncompressed audio, Apple introduced AIFF-C which can use MACE and IMA/ADPCM compression with ratios as high as 6:1, but the audio sound quality suffers.