What are freckles?

You may have been told as a child that they are angel kisses. But, really -- what are freckles?

Those little brown spots adorning your body are merely patches of pigment, called melanin. This freckle ingredient protects your skin from the sun's damage by reflecting and absorbing ultraviolet (UV) rays.

Freckles owe their mark to genetics and sun exposure. Genetics appears to play a significant role in who has freckles to begin with. In fact, identical twins have a striking similarity in the number of spots that dot their bodies.

The sun's rays fuel melanin production. This is your skin's way of preparing your body for future tropical outings. So for some people, a day in the sun may lead to more freckles rather than the desired bronze tan.

Originally published on Live Science.