Hyperpigmentation is a condition in which the skin produces more melanin (the pigment which gives skin its colour). This causes some patches of the skin to appear darker than the surrounding areas. This is a common skin condition, affecting people of all skin types. A few types of hyperpigmentation, such as melasma and sun spots, usually affect areas of the skin that face sun exposure (mostly the face, arms and legs). Some other types usually occur after an injury or skin inflammation such as cuts or burns. Extra pigmentation in some areas of the skin is considered harmless but it can sometimes be a sign of an underlying medical condition.