4 September

Next time you're queued at the lights, watch what happens when they go green. The cars will move off one at a time, from the front, each one waiting for the one ahead to move first. This isn't necessary, technically all cars could move off at the same time. (Car racing does this.) But this is why traffic jams happen, more generally, individual drivers respond only to their immediate surroundings, rather than to the wider conditions. There would be multiple ways to network cars to stop this from happening. Those ways are all coming.