Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin where patches of the skin turn into a darker shade of colour due to excessive presence of melanin, found on skin surface.
It’s these ageing dark spots of bother that is known as pigmentation, caused by sun exposure and specifically the UVA rays which penetrate deep into your skin and cause ageing.
UVA stimulates your pigment cells called Melanocytes to manufacture the pigment called Melanin. This is responsible for your tan and also your unwanted dark patches. These sun spots may take up to 10-20 years to develop, so if you notice some showing now it could have been caused when you were a child.