Plug-ins can be broken down into the following categories:
Audio effects: Can be inserted in audio, instrument, aux, and output channel strips. Logic Pro offers a range of digital signal processing (DSP) effects and processors that are used to color or tonally shape existing audio recordings, software instruments, and external audio sources—in real time.
MIDI effects: Can only be inserted in instrument channel strips. Logic Pro offers easy access to real-time MIDI processing formerly only possible via the Environment.
Software instruments: Can only be inserted in instrument channel strips. Logic Pro offers a range of software-based instruments that include innovative synthesizers, a powerful sampler, and authentic re-creations of vintage instruments, that can be used in real time.
GarageBand instruments: Can only be inserted in instrument channel strips. GarageBand instruments are accessed by holding down Option when clicking an Instrument slot.