 boids is an artificial life program, developed by craig reynolds in 1986, which simulates the flocking behaviour of birds. his paper on this topic was published in 1987 in the proceedings of the acm siggraph conference. the name "boid" corresponds to a shortened version of "bird-oid object", which refers to a bird-like object. its pronunciation evokes that of "bird" in a stereotypical new york accent. as with most artificial life simulations, boids is an example of emergent behavior; that is, the complexity of boids arises from the interaction of individual agents (the boids, in this case) adhering to a set of simple rules. the rules applied in the simplest boids world are as follows: * separation: steer to avoid crowding local flockmates * alignment: steer towards the average heading of local flockmates * cohesion: steer to move toward the average position (center of mass) of local flockmates more complex rules can be added, such as obstacle avoidance and goal seeking. the basic model has been extended in several different ways since reynolds proposed it. for instance, delgado-mata et&nbsp;al.  extended the basic model to incorporate the effects of fear. olfaction was used to transmit emotion between animals, through pheromones modelled as particles in a free expansion gas. hartman and benes  introduced a complementary force to the alignment that they call the
Artificial_life