An AUDIONOTE file is a note created by AudioNote, a macOS (Mac OS X) application used to record notes and audio. It contains a voice recording synced with notes, which may include text, drawings, and pictures. AUDIONOTE files are used to take better notes during meetings, study sessions, interviews, and lectures.

You can open and listen to an AUDIONOTE file using the AudioNote application. However, if you do not own the program and are a Windows user you can convert the AUDIONOTE file. Rename the ".audionote" extension to ".rar" or ".zip" and right-click the file to extract its contents. There will be multiple files after the extraction, including the .CAF audio file. There are several programs available to open the CAF file or you can convert it to another format such as .MP3.