Shading refers to the depiction of depth perception in 3D models or illustrations by varying the level of darkness. In visual art, shading is used traditionally in drawing for depicting a range of darkness by applying media more densely or with a darker shade for darker areas, and less densely or with a lighter shade for lighter areas. Light patterns, such as objects having light and shaded areas, help when creating the illusion of depth on paper. In computer graphics, shading refers to the process of altering the color of an object/surface/polygon in the 3D scene, based on things like the surfaces angle to lights, its distance from lights, its angle to the camera and material properties to create a photorealistic effect. Shading is performed during the rendering process by a program called a shader.

Apart from the above definition, the term "shading" can also refer to a slight variation or difference of color, character, etc. . In addition, "shading" can also mean leaving without permission, leaving work early, or avoiding undesirable work.