  The movement of pedestrians is supposed to show certain regularities which
can be best described by an ``algorithm'' for the individual behavior and is
easily simulated on computers. This behavior is assumed to be determined by an
intended velocity, by several attractive and repulsive effects and by
fluctuations. The movement of pedestrians is dependent on decisions, which have
the purpose of optimizing their behavior and can be explicitly modelled. Some
interesting applications of the model to real situations are given, especially
to formation of groups, behavior in queues, avoidance of collisions and
selection processes between behavioral alternatives.
