Audacity is a free and open-source digital audio editor and recording application software, available for Windows, macOS, Linux, and other Unix-like operating systems. The project was started in the fall of 1999 by Dominic Mazzoni and Roger Dannenberg at Carnegie Mellon University, and released on May 28, 2000, as version 0.8. As of December 6, 2022, Audacity is the most popular download at FossHub, with over 114.2 million downloads since March 2015. It was previously served from Google Code and SourceForge, where it was downloaded over 200 million times. Audacity won the SourceForge 2007 and 2009 Community Choice Award for Best Project for Multimedia. It is licensed under GPL-2.0-or-later. In 2019, then-lead developer James Crook started the fork DarkAudacity to experiment with a new look and other UX changes. Most of its changes were eventually incorporated into the mainline version and the fork ended. In April 2021, it was announced that Muse Group (owners of MuseScore and Ultimate Guitar) would acquire the Audacity trademark and continue to develop the application, which remains free and open source. Features and use In addition to recording audio from multiple sources, Audacity can be used for post-processing of all types of audio, including effects such as normalization, trimming, and fading in and out. It has been used to record and mix entire albums, such as by Tune-Yards. It is currently used in the Sound Creation unit of the UK OCR National Level 2 ICT course. Audacity's features include: Recording and playing back sounds Timer Record – schedule when a recording begins and ends, for unattended recording Punch and Roll recording – for editing on-the-fly (version 2.3.0 on) Scrubbing (audio) (Version 2.1.1 and later) MIDI playback (version 2.2.0 on) Editing Via cut, copy, and paste, with unlimited Undo levels Smart clips (version 3.2.0 on) Non-destructive trimming (and un-trimming) of audio clips Real-time effects (version 3.2.0 on) Non-destructive and destructive effect processing. Multi-track features including navigation controls, zoom and single-track edit, project pane and XY project navigation. Amplitude envelope editing Precise adjustments to speed (tempo) while maintaining pitch, to synchronize audio with video or for precise running time Conversion of records, tapes or MiniDiscs to digital tracks by splitting the audio source into multiple tracks based on silences in the source material Cross-platform operation – versions for Windows, macOS (Intel, ARM and Universal builds) and Unix-like systems (including Linux and BSD). It uses the wxWidgets software