# MIDI control overview

There are several ways that Liberation uses MIDI:

* As a live controller, with the APC 40. See [live-control-with-the-apc40](https://docs.liberationlaser.com/midi-control/live-control-with-the-apc40 "mention").
* As a clock sync source, using MIDI clock and MIDI song position messages. See [#midi-clock](https://docs.liberationlaser.com/tempo-synchronisation#midi-clock "mention")
* As an interactive input on the MIDI notes node to create "laser harp" style effects. See [midi-notes](https://docs.liberationlaser.com/clip-editor/operator-nodes/midi-notes "mention")
* As a more general input/output system using the MIDI Send/Receive system. See [midi-send-receive](https://docs.liberationlaser.com/midi-control/midi-send-receive "mention")