Well, cars came into being at first as steam driven, but the weight was high and there were no hard roads, so they got along on tracks = rail road. Later smalle

Well, cars came into being at first as steam driven, but the weight was high and there were no hard roads, so they got along on tracks = rail road. Later smaller gasoline driven machines came along (first Benz) and it advanced because it freed us from costly, maintenance intensive, food intensive and crap/pee intensive horses. Before cars many large city street were 2-3 feet deep in horse shit. As for control, huge latency issues would hinder large amounts of traffic.