Ultraviolet rays do a lot of damage to the skin, causing skin aging, spots, and possibly sunburn. 1. Skin aging: ultraviolet light irradiation of the skin will cause collagen and elastin within the skin to decompose and denature, but also lead to abnormal deposition of elastin fibers, resulting in skin aging, also known as photoaging. 2. Spotting: UV rays can promote melanin synthesis, thus causing hyperpigmentation, and long-term exposure to UV rays will increase the occurrence of melasma and other pigmented spots. 3. Sunburn: Sunburn is an inflammatory reaction caused by excessive exposure of the skin to ultraviolet rays, and the patient will suffer from localized redness, swelling, burning and pain, which is also clinically known as solar dermatitis. It is recommended to go out to do sunscreen measures to avoid long-term exposure of the skin to ultraviolet radiation.