What are gps systems and what are they good for?

Famous quotes containing the word systems:

    We have done scant justice to the reasonableness of cannibalism. There are in fact so many and such excellent motives possible to it that mankind has never been able to fit all of them into one universal scheme, and has accordingly contrived various diverse and contradictory systems the better to display its virtues.
    Ruth Benedict (1887–1948)