Here's some explanation of what happens in the car:
A laser range finder mounted on the roof of the car generates detailed 3D map of the surroundings. Four radars, mounted on the front and rear bumpers, that allow the car to deal with fast traffic on roads; a camera, positioned near the rear-view mirror, detects traffic lights. GPS, inertial measurement unit, and wheel encoder, that determine the vehicle's location and keep track of its movements.
All these technologies work together to drive a car. Chris Urmson and