The program CA.html creates images that show the evolution of one-dimensional cellular automata over time. (What this means is explained below.) A set of rules for an automaton is generated randomly when you click "Create New Rule Set Using". Only some of the rules in the set are active; the slider at the top determines how many are active. When very few are active, the image tends to be boring, with the colors either dying out or repeating in a simple pattern. When most of the rules are active, the image again tends to be boring, but this time because the pattern is too chaotic. Maybe somewhere between, at the "edge of chaos," you can get interesting and beautiful patterns.