Shading refers to the depiction of depth perception in 3D models (within the field of 3D computer graphics) or illustrations (in visual art) by varying
graphics, Phong shading, Phong interpolation, or normal-vector interpolation shading is an interpolation technique for surface shading invented by computer
Cel shading or toon shading is a type of non-photorealistic rendering designed to make 3D computer graphics appear to be flat by using less shading color