Ray tracing is a method for modeling light transport in 3-D computer graphics that may be applied to a wide range of rendering techniques to produce digital images.

Ray tracing-based rendering techniques, such as ray casting, recursive ray tracing, distribution ray tracing, photon mapping and path tracing, are typically slower and more accurate than scanline rendering approaches on a spectrum of computing cost and visual fidelity. As a result, ray tracing was initially used in rendering-intensive applications like still CGI images and visual effects (VFX) for film and television, but it was less suitable for real-time applications like video games, where frame rate is crucial.

However, since 2019, real-time ray tracing hardware acceleration has become a requirement for new commercial graphics cards, and graphics APIs have followed suit. This enables developers to use hybrid ray tracing and rasterization-based rendering in games and other real-time applications with a smaller impact on frame render times. Numerous optical effects, reflection, refraction, soft shadows, scattering, depth of field, motion blur, caustics, ambient occlusion and dispersion phenomena (such as chromatic aberration). The ability to generate realistic reverberation and in echoes makes it a feasible choice for more immersive sound design in video games. It may also be used to trace the path of sound waves in a manner similar to how light waves are traced. In fact, any physical wave or particle phenomenon with approximately linear motion can be simulated with ray tracing.