Tanning acts as a defense mechanism of the skin against ultraviolet rays. When the UV rays touch the skin, the melanocytes increase the production of melanin, which absorbs the rays, protecting the inner layers of skin from damage. This is a temporary, homogeneous darkening process that usually follows the areas exposed to sunlight and gradually fades once further sun exposure is reduced. Dark spots, on the other hand, point to a more serious pigmentation problem, such as melasma, post-inflammatory hyperpigmentation, or solar lentigines. These do not always resolve with time alone because the underlying trigger, such as hormonal fluctuation, an old acne scar, or repeated micro-injury to the skin, continues to stimulate melanin production in specific patches rather than uniformly across the exposed area.