Toom's rule is a 2-dimensional cellular automaton model created by Andrei Toom in 1978 (see for an English translation). This model is both more robust and simpler than the 2-dimensional majority vote rule (see for more details). Toom's rule is a cellular automaton that acts on a 2-dimensional square lattice. At each site in this lattice is a spin with the value +1 or -1. At time the bits are initialized to some value. At each discrete time step the lattice evolves according to Toom's rule. This rule is applied at each site simultaneously.