Cellular automata can process information when their collective global behavior exceeds the sum of the behaviors of their individual cells. Information processing emerges from cooperation of the individuals, who must be able to communicate in a meaningful manner. Class I, II, and III automata fail to provide a substrate for meaningful communication. I and II, information is confined locally, and is simply not transmitted. In class III, by contrast, information is meaningfully transmitted only over short distances in space and time.
Deterministic chaos injects noise at a significant rate, washing out all signal.
Class IV automata form the intermediate case, not too hot, not too cold. He found that the values of the various observables often served to separate rules into clusters with certain properties. The results of an experiment in this spirit is shown in figure 4 . To produce this figure, CA were simulated. In the figure these values are represented by the horizontal axis, the vertical axis, and a color scale, respectively.