Audio plug-in

Such functions may include digital signal processing or sound synthesis.

[1][page needed] Audio plug-ins usually provide their own user interface, which often contains graphical user interface (GUI) widgets that can be used to control and visualize the plug-in's audio parameters.

Example hosts include Bidule, Gig Performer, Mainstage, REAPER, and Sonic Visualiser.

The specification may also include documentation about the meaning of variables and data structures declared in the API.

The API header files, specification, shared libraries, license, and documentation are sometimes bundled together in a software development kit (SDK).