Sunscreens are classified as both organic, or chemical, and inorganic, or physical. Organic compounds, such as oxybenzone and octinoxate, work like sponges to absorb UV radiation. Inorganic compounds, containing zinc oxide and/or titanium dioxide, shield the skin to reflect and scatter UV radiation. A broad-spectrum sunscreen contains compounds that absorb and/or reflect UVB rays in addition to Ultraviolet A (UVA) rays, the ones that age skin and cause wrinkles. Many types of sunscreens in the U.S. combine organic and inorganic compounds to provide this kind of broad-spectrum protection.