When a Map Pane displays a GPS track, that track will be drawn in the first color available from the following list:
Here you can see that the first three tracks are adopting the color assigned to the first tag for that track. The (tag) text inside the color column also indicates this. The last track has been assigned a track specific color, a light pink in this case, and the color column displays (track) to indicate the track specific color.
The track lines on the Map Pane will use this color when drawing the track. This makes it easy to visually distinguish groups of related tracks, such as hiking tracks, or aircraft tracks.