How to convince others ? Monte Carlo simulations of the Sznajd model

In the Sznajd model of 2000, a pair of neighbouring agents on a square lattice convinces its six neighbours of the pair opinion if and only if the two agents of the pair share the same opinion. It differs from other consensus models of sociophysics (Deffuant et al., Hegselmann and Krause) by having integer opinions like $\pm 1$ instead of continuous opinions. The basic results and the progress since the last review are summarized here.