Readers familiar with the Game of Life (see our main page; if not already familiar, visit our introduction) are probably aware of the existence of a number of "otherworlds": cellular automata similar in nature(1) to the Game of Life, but where the rules for when cells survive or are born are different, resulting in patterns and structures with very surprising appearances and behavior. The purpose of this page is to present a number of such universes that seem to be extremely fascinating.
Due to the large amount of available information, rather than putting everything in a single page, we prefer to devote individual pages to each of those cool universes. Click on any of the pictures, below, to move to the page where the corresponding world is described. For another view at classification of cellular atomata we encourage the reader to take a look at David Eppstein's classification (see bottom of his page). However, we follow our own empirical "classification" below, because we are unable to characterize with certainty every case presented here as belonging to one of Prof. Eppstein's four classes.
1. Cellular automata such as Conway's Game of Life and all the automata presented here belong to the class of totalistic cellular automata, so called because in order to find whether a cell will be born, survive, or die, we count its alive neighbors and base our decision on the total sum of that counting. Another possibility is to take into account the specific location of some neightbors. (E.g., to state that a cell is born if its upper and lower-left neighbors are simultaneously alive.) Still other possibilities are to count more than the immediate eight neighbors, to allow more than two states for each cell (i.e., alive and dead), to work in less or more than two dimensions, to work with a non-orthogonal space (e.g., hexagonal), and so on.