Automation
Automation Tracks are sub-tracks for an audio or MIDI track that allows automated/programmed control over some parameter that affects how that track will sound. A single track can have multiple automation tracks, with each one controlling a distinct parameter. Common parameters to control are volume and pan. Depending on the track, other items might be controled, such as pitch (for advanced pitch-shifting), resonance and cutoff frequency for a synthesizer, and other key parameters of effects like reverb, delay, EQ, and compression.
Automation tracks typically look similar to a normal track - a long horizontal rectangular box; however, while a MIDI track has MIDI information/notes and an audio track has a visualization of the audio, an automation track contains a series of lines connected by points. By default, there may not be any points at all, only a single line at about 80%. You move the line up and down to adjust the parameter - higher in the box means a higher value. You can also add points to make the value change over time, which can be gradual or immediate. For example, you can make volume gradually fade in or out or have it toggle on and off like a stutter effect.