A plugin is a software synthesizer which can be accessed within a DAW. Usually the plugin is loaded on a MIDI track.
Instrument plugins interface with your DAW through one of a handful of standards. Steinberg's VST is a standard supported by many DAWs. AudioUnit (AU) is widely supported on Mac computers. RTAS is used by ProTools. Put simply, you should check your DAW's user manual to see what kind of plugins you can run.
Instrument plugins interface with your DAW through one of a handful of standards. Steinberg's VST is a standard supported by many DAWs. AudioUnit (AU) is widely supported on Mac computers. RTAS is used by ProTools. Put simply, you should check your DAW's user manual to see what kind of plugins you can run.