A typical control area for an audio track is shown below:
An audio track has the same controls as a bus, with the addition of two extras. The red button with the pink circle is the track's record enable. When this is clicked it will gain a bright red outline, and the track will then be recorded onto when the main session record enable is turned on with the transport rolling.
The ‘p’ button below the record enable will open a playlist menu when clicked. The menu offers various operations related to the track's playlist. This, as you will recall, is simply a list of the regions that the track should play. Playlists may be swapped on a given track, and may be used by more than one track at the same time. They are often useful to keep different takes, for example, or to allow one set of regions to be played off two tracks with different processing.