Path tracing is the uncompromising version of ray tracing. Instead of selectively ray-tracing certain effects like reflections or shadows, path tracing traces full light paths from the camera through the scene, bouncing off surfaces multiple times until they reach a light source or are absorbed. Every reflection, refraction, shadow, caustic, and instance of global illumination emerges naturally from the simulation rather than being a separate, approximated effect. The result is lighting that is physically correct by definition, matching real-world behavior exactly. The challenge is performance: path tracing requires tracing millions of rays per frame, each bouncing multiple times, which demands enormous GPU power. Real-time path tracing has only become feasible with modern RTX hardware combined with AI denoising that cleans up the inherently noisy results of sampling limited light paths.