Boids is a flocking simulation program, first designed by Craig Reynolds in 1986 and published in 1987. The name comes from "bird-oid objects", or "bird-like objects."

The world that they fly in is a torus, meaning that it wraps top to bottom and left to right. In addition, each boid is colored based on its heading.

There are three main rules that the individual boids follow:

• Separation: Steers to avoid nearby boids
• Alignment: Steers to move in the same direction as nearby boids
• Cohesion: Steers toward the center of mass of nearby boids

You can use the sliders below to change how relatively important each rule is to the boids.