When your NAV system is online and you are in PARK you can bring up the "GPS Information" page. It displays a graphic image of how many SAT signals you are receiving relative to your position and roughly where the satellites are in orbit above you. If you receive at least 3 SAT signals at once that page will also popup your exact Lat/Long and even altitude. Very cool.
If you leave that page displayed then put the tranny in drive you can motor around with that screen up. If you change pages while driving you loose that screen and may have to return to PARK to bring it up again.
This is very similar to a GPS flight guidance computer for aircraft. I work with those everyday as well but they are much more complicated with flight plans, traffic collision avoidance systems, weather radar ect, ect.
Regards,