Important points about the illumination Model
An illumination model is also termed as lighting model and sometimes considered to as shading model, that is utilized to compute the intensity of the light wihch is reflected at a specified point on the surface of an object, while the Surface rendering algorithm utilizes the intensity calculations from an illumination model to verify the light intensity for each projected pixel position for the different surfaces in the scene. By the above discussion we have realized about its types of light source which contributes many towards the attainment of realism in any computer graphics scene.