When a GPS-equipped bus approaches an intersection, it can, as before, take over the intersection's traffic light, but thecomputer can also calculate its expected time of arrival and decide either to extend a green light or shorten a red light.
Imagine if every time you got into your car to go somewhere, hundreds of people already out on the road reported on thetraffic ahead of you, and a computer somewhere processed all they did and saw and calculated the fastest route to your destination right at this instant, and even instantly updated it as you drove, when those other drivers indicated that conditions changed.
For example, the National Air Traffic Service, which has presided over one of the worst computer-procurement failures at its much-delayed Swanwick control centre, is outside parliamentary audit.