In the universal cellular automaton that we discussed earlier in this chapter, each of the various kinds of components involved in its operation had properties that were explicitly built into the underlying rules. Indeed, in most cases each different type of component was simply represented by a different color of cell. But in rule 110 there are only two possible colors for each cell. So one may wonder how one could ever expect to represent different kinds of components.

A typical example of the behavior of rule 110 with random initial conditions. From looking at pictures like these one can begin to imagine that it could be possible to arrange localized structures in rule 110 so as to be able to perform meaningful computations. Note that page 292 already showed many of the types of localized structures that can occur in rule 110.