To create true (photorealistic) reflections, you must raytrace the scene, a process which can take a significant amount of time, depending on the complexity of your scene. To optimize raytracing to reduce rendering times you can limit the number of reflections per surface and which surfaces reflect.
Raytracing is a type of shadow rendering where the path of individual light rays are calculated from their source (the light) to their destination (the camera). For more information on raytracing, see Depth map and raytraced shadows in the Lighting guide.
To create true reflections, see Create true reflections. See also Create blurry reflections using mental ray for Maya.
