content: For a long while, self-driving cars will mainly be in control on highways and not on city streets. There are less variables on the highway than on city streets. On the highway, you only only have to worry about the speed and distance of the car in front of you and any cars next to you when you want to change lanes. On city streets, you have stop lights, stop signs, blinking red lights, people stopped in the road, train crossings, etc. For stuff like stop signs, you could just have every government stop sign and traffic light location in the car's computer and it'll stop at the intersection