A state machine that consists of an array of cells, each of which can be in one of a finite number of possible states. The cells are updated synchronously in discrete time steps, according to a local, identical interaction rule. The state of a cell at the next time step is determined by the current states of a surrounding neighborhood of cells. The transitions are usually specified in the form of a rule table that defines the cell's next state for each possible neighborhood configuration. The cellular array (grid) is typically from one to three dimensions. Highly parallel, locally connected and using simple elemental units, cellular automata can perform so-called cellular computing. See state machine.