Ray Casting is a computer graphics technique used to determine the visibility of objects in a scene. It works by projecting rays from a viewpoint into the environment and checking for intersections with objects. This method helps in rendering images by calculating which surfaces are visible and how they should appear. In video games and simulations, Ray Casting is often used for collision detection and to create realistic lighting effects. By tracing rays, developers can simulate how light interacts with surfaces, enhancing the visual quality of the scene. This technique is foundational for more complex rendering methods like Ray Tracing.