I thought AIFF was Apple's format, not Microsoft's.
Wave is Microsoft's, right?
Edit: From Wikipedia
Audio Interchange File Format (AIFF) is a audio file format standard used for storing sound data on personal computers. The format was co-developed by Apple Computer based on Electronic Arts Interchange File Format (IFF) and is most commonly used on Apple Macintosh computer systems. AIFF is also used by Silicon Graphics Incorporated.
The audio data in an AIFF file is uncompressed big-endian pulse-code modulation (PCM) so the files tend to be much larger than files that use lossless or lossy compression formats such as APE and MP3. The AIFF-Compressed (AIFF-C or AIFC) format supports compression ratios as high as 6:1.
WAV (or WAVE), short for WAVE form audio format, is a Microsoft and IBM audio file format standard for storing audio on PCs. It is a variant of the RIFF bitstream format method for storing data in "chunks", and thus also close to the IFF and the AIFF format used on Macintosh computers. It takes into account some peculiarities of the Intel CPU such as little endian byte order. The RIFF format acts as a "wrapper" for various audio compression codecs. It is the main format used on Windows systems for raw audio.