ELI5: Explain Like I'm 5

Ray tracing (graphics)

Okay, so imagine you are drawing a picture. You start by drawing the outline of an object, like a house or a car. Then, you add colors and shading to make it look more realistic. Ray tracing is like that, but it's done by a computer to create graphics for movies, video games, and other things.

Instead of starting by drawing an outline, a computer uses thousands of tiny beams of light (called rays) to create a 3D model of whatever it is making. These rays bounce around the virtual space, hitting different objects in the scene and bouncing off in different directions.

As each ray bounces around, the computer calculates how it interacts with the objects it hits, including things like reflection, refraction (when the ray bends as it passes through different materials), and shadows. By doing this for every single ray, the computer creates a realistic scene that looks like it has depth and texture.

Think about it like going into a dark room with a flashlight. As you move the flashlight around, you can see things in the room - but not everything is lit up. The same is true for ray tracing. Some objects in the scene might be brighter or darker, depending on where the rays hit.

Overall, ray tracing is a really cool way for computers to create realistic looking graphics that have lots of depth and texture - and it's used in tons of movies and video games that you might love!