Tracks inspector
You can examine all the tracks in a file by navigating to the Tracks pane using the main toolbar.
This is what it might look like

As you can see this movie has 2 tracks, a Video Track and a Sound Track. There are many different kinds of tracks you can see in this view for example; Video, Sound, Text, Sprite, Tween, Hint, MPEG, Flash, QTVR, Quartz Composer or MIDI. You will get more info about each track by selecting it in the list.