Audio Interchange File Format (AIFF) is a format developed by Apple in 1987-88 in accordance Electronic Arts Interchange File Format (IFF) standards.
It can store monaural, stereo or multi-channel sound in PCM format.
It is a lossless format and no compression is applied.

It is Apple's equivalent of WAV
AIFF is big-endian (most-significant byte first) and this corresponds with the processor architecture used  by Apple (Power PC=big-endian).
Apple has created a new version of AIFF in little endian.

This is the format used on Intel based Mac’s.

  1. Audio Interchange File Format - WikipediA
  2. Audio Interchange File Format - Apple Computer, Inc