Types of Light Resources - illumination Model

Let us discuss about the types of light resources. The light sources can not merely be natural like light from Sun or Moon or Stars although this could be man-made devices as like tube or bulb and so no, or a highly polished surface. The light resources are considered as Luminous objects that are the objects which emit radiant energy and they can be of both kinds light emitting source that could be of any form point/diffuse or distributed objects emitting radiant energy) and a light reflecting source as Reflecting surfaces are occasionally considered to as light reflecting sources, which is any polished surface able of reflecting, a referred amount of light rays.