shown in other instead.
Spot Light Source
The spot light radiates light from a single infinitely small point in a circular, uniform spread (360 degrees) and is similar to the omni light source. However, unlike the latter, spot light cannot cast shadows. These sources are rendered in a bunch of four, thus requiring substantially lesser render passes. Considering the mentioned fact, spot lights are fast and eminent for very low performance cost.
This type of sources effectively serve as fill lights that brighten shadows and optimize scene illumination. When used in combination with lightmaps and set to moderate radius, spot light grant pictorial specular reflections.