Collision detection is the problem of determining if geometric objects intersect. It is an important topic in computer graphics, in CAD/CAM, in dynamical simulation, and in computer games.

- Stackoverflow.com Wiki
1 articles, 0 books.

In order to more realistically simulate the behavior of solid objects, we have to check if they collide with each other every time they move, and if they do, we have to do something about it, such as applying forces that change their velocities, so that they will move in the opposite direction.