Diffuse Light

Diffuse Light

Ambient Light

Light from everywhere.

Diffuse + Ambient (lights the previously black as well as everything else).

Specular Light / Specular Highlight

The specular highlight makes the object seem to reflect light.

Diffuse + Ambient + Specular:

Images from http://www.directxtutorial.com/Lesson.aspx?lessonid=9-4-3