Beyond 184 is a cellular automata for simulating traffic in an urban setting.
Every single one of those little cars is not just going in a straight line, but is instead behaving similarly to an actual car – accelerating as they move through an empty road, and slowing down before obstacles.
It is based on the Rule 184 CA (hence the name), with enhancements made to add varying speed levels and to make the whole thing work in two dimensions.