So yeah, "Cellular Automaton" is a thing. The basic idea is analogous to John Conway's "Game of Life." The idea is to model a system you want to investigate using an regular grid or tessellation of "cells" and apply relatively simple rules iteratively. The macro evolution of the system as produced by the interaction of cells through time can be a useful numerical tool to investigate many areas of physics, biology and other sciences. In this simulation there is no gravity or forces between cells! It is just the interaction of turning them on and off based on simple rules. For the full story see: I M P O R T A N T ! (best/Correct version) Please also see another run of the code with different settings that allow you to clearly see the updating cells!