What is an au file?

An AU file is an audio file format used on Mac operating systems, also known as Audio Interchange File Format (AIFF). AU files contain audio data in a non-compressed or lossless format, which means the audio quality is preserved during playback.

The format was introduced in the early 90s by Sun Microsystems and has been widely used for professional audio recording and editing.

AU files can be played back on most media players and audio software, including Apple's QuickTime Player, iTunes, and Adobe Audition. However, due to their large size compared to compressed audio formats, they are less commonly used for online streaming or distribution.