Melanin

Brown pigment that shields against ultra violet light by absorbing the light energy. People with dark or black skins will have more and larger melanin granules then those of light-skinned people.

Melanin is a dark pigment that is released into your skin when you get a tan. Melanin is produced in skin cells called melanocytes. U.V. radiation from the sun stimulates the melanocytes. They start producing new melanin granules. The new melanin granules are transferred to upper cell layers of the skin. The pigment builds up in your cells to provide a more protective barrier against the sun. The result is darker skin.

Sun Protection Factor (SPF)

Some foundations offer an SPF (sun protection factor) as added protection for brief exposure to the sun. However, a separate sunscreen of SPF 15+ should be used if you intend to stay out in the sun for any period of time, e.g. doing sports activities.