Track name

The top black area filled up with alphanumeric symbols (in this case Audio1).

Gain fader

the strip just below the track name

Record button

the red dotted button to enable/disable recording on that track

Mute button

m

Solo button

s

Playlist button

p

Automation button

a

Edit Group button

g

Meter

the strip on the right side

Height

Change the height of the track, which can also be changed by dragging the symbol

Color

Change the color of the regions in the track's playlist. An alternating default color is picked for every new track

Remote control ID

Defines the order of channels when they appear on an external controller (such as a MIDI fader controller)

Automation

Select which automation tracks are shown

Hide/Show all crossfades

Toggle display of crossfades of all regions in the track's playlist

Waveform

Draw waveforms logarithmic or linear; rectify waveforms or not

Alignment

Determines whether to align a recording with ardour's pre-recorded material (by accomodating delays in the playback delays) or not

Normal/Tape mode

See Tape mode for details

Active

Inactive tracks do not record, process or play back any audio

Hide

Hide this track from the Editor window

Remove

Delete this track, including all playlists, routing and plugins. Audio recorded on this track remains in the region list