Editing Audio Interchange File Format (section)

==AIFF on macOS==
{{Original research|section|date=March 2009}}

With the development of the OS X operating system now known as [[macOS]], Apple created a new type of AIFF which is, in effect, an alternative [[little-endian]] byte order format.<ref>{{Cite web |date=2008-10-29 |title=Speech Synthesis Manager - OS X Manual |url=https://developer.apple.com/mac/library/documentation/Darwin/Reference/ManPages/man1/say.1.html |url-status=dead |archive-url=https://web.archive.org/web/20091128075236/https://developer.apple.com/mac/library/documentation/Darwin/Reference/ManPages/man1/say.1.html |archive-date=2009-11-28 |website=Apple}}</ref><ref>{{Cite web |date=2008-11-13 |title=Supported Audio File and Data Formats in Mac OS X |url=https://developer.apple.com/iphone/library/documentation/musicaudio/Conceptual/CoreAudioOverview/SupportedAudioFormatsMacOSX/SupportedAudioFormatsMacOSX.html |url-status=dead |archive-url=https://web.archive.org/web/20090523155253/https://developer.apple.com/iphone/library/documentation/musicaudio/Conceptual/CoreAudioOverview/SupportedAudioFormatsMacOSX/SupportedAudioFormatsMacOSX.html |archive-date=2009-05-23 |website=Apple}}</ref>

Because the AIFF architecture has no provision for alternative byte order, Apple used the existing AIFF-C compression architecture, and created a "pseudo-compressed" codec called '''sowt''' ('''twos''' spelled backwards). The only difference between a standard AIFF file and an AIFF-C/sowt file is the byte order; there is no compression involved at all.<ref name="RF04">{{cite web |date=1995-05-01 |title=Technical Q&A QTMRF04: QuickTime Sound |url=https://developer.apple.com/library/archive/qa/qtmrf/qtmrf04.html |url-status=live |archive-url=https://web.archive.org/web/20220705133320/https://developer.apple.com/library/archive/qa/qtmrf/qtmrf04.html |archive-date=2022-07-05 |access-date=2009-11-09 |website=Apple |publisher=}}</ref>

Apple uses this new little-endian AIFF type as its standard on macOS. When a file is imported to or exported from [[iTunes]] in "AIFF" format, it is actually AIFF-C/sowt that is being used. When audio from an audio CD is imported by dragging to the macOS Desktop, the resulting file is also an AIFF-C/sowt. In all cases, Apple refers to the files simply as "AIFF", and uses the <code>.aiff</code> extension.

For the vast majority of users this technical situation is completely unnoticeable and irrelevant. The sound quality of standard AIFF and AIFF-C/sowt are identical, and the data can be converted back and forth without loss. Users of older audio applications, however, may find that an AIFF-C/sowt file will not play, or will prompt the user to convert the format on opening, or will play as static.

All traditional AIFF and AIFF-C files continue to work normally on macOS, and many third-party audio applications as well as hardware continue to use the standard AIFF big-endian byte order.