A Majority Automata consists of applying over the vertices of a undirected graph (with states 0’s and 1’s) an operator that chooses the most represented state among the neighbors of a vertex. This rule is applied in parallel over all the nodes of the graph. When the graph is a regular lattice ( in one or more dimensions) it is called the Majority Cellular Automata. In this seminar we will study the computational complexity of the following prediction problem: PRED: Given an initial configuration and a specific site initially at state a ( 0 or 1), is there a time step T≥1 such that this site changes state? The complexity of PRED is characterized by the possibility to find an algorithm that give the answer faster than the running of the automata simulation in a serial computer. More precisely, if we are able to determine an algorithm running in a parallel computer in polylog time (class NC). Otherwise, the problem may be P-Complete ( one of the most dificult in class P of Polynomial problems) or … worse. We will applied this kind of results to the discrete Schelling’s segregation model. Also we will present the Sakoda’s Social Discret model.