Automation refers to recording, editing, and playing back the movements of faders, knobs, and switches. Using automation, you can create changes over time to volume, pan, and other settings. You can add automation to all track types.
Each track in your project has automation curves for volume and pan, and you can add curves to automate plug-in settings. To create changes over time, you do the following:
Show the automation curve you want to work on, and choose between track-based and region-based automation.
Add automation points to the curve at the start and end points for the change you want, then adjust the automation points.