Furuno GP-31 Operator's Manual page 12

Plotter display
The plotter display traces own ship's track, and shows position, course, speed, and hori-
zontal display range setting.
Figure 1-4 Plotter display
Highway display
The highway display provides a 3-D view of own ship's progress toward destination. Nav
data is also shown.
Figure 1-5 Highway display
1-4