Specular reflection is the reflection of light from a smooth surface that is reflected to the opposite angle of the original light source. Reflected light is reflected directely to the original light source only if refllected at a 90C angle to the light source.

Diffuse reflection is the that of light from a rough surface. Even though light is reflected, the object which has the rough surface cannot be recognized well.

Retroreflection occurs when surfaces return the directed light to its source. This is why retro-reflective materials appear brightest to observers located near the light source. For example, a person who drives a car using vehicle headlights can view any angle, which makes retro-reflective surfaces excellent for night visibility.