Sunscreen is a product that protects the skin from the sun's harmful UV rays. It is typically applied topically to the skin and works by absorbing or reflecting the sun's ultraviolet (UV) radiation. Sunscreen is available in various forms such as lotions, creams, sprays, and gels, and is available in different strengths or "SPF" (sun protection factor) levels. The higher the SPF, the more protection the sunscreen provides against UVB radiation, which is the main cause of sunburn and skin cancer. Sunscreen is an essential product for anyone spending time outdoors, and it is recommended to apply it at least 15-30 minutes before sun exposure and to reapply every 2 hours or after swimming or sweating.