Shadows are produced when light hits an opaque object which prevents the light beams from passing through. When an object blocks the light's path, then darkness appears on the other side. This darkness is called a shadow. The sun is a source of light that when hits an object causes shadows.
Explanation:
Light and shadows visually define objects. ... Artists use values to translate the light and shadows they see into shading, thus creating the illusion of a third dimension. Hatching and crosshatching are simple and fun techniques for drawing shading. A full range of values is the basic ingredient for shading.
