Take note that a car navigation device does not know of short cuts, present traffic situation or traffic lights. Installing the GPS in your car does not necessarily mean that you quit using your mind. The news on television has informed us occurrences of motorists who adopted the Gps navigation unquestioningly and wound up causing traffic mayhem and some result in tragedy. Occasionally traffic rules change that is why we need to heed the actual traffic rule rather than sticking to a contrary instruction by your GPS to avoid trouble.