Sunscreens are topically applied products that protect the skin from the sun's damaging ultraviolet (UV) radiation. Sunscreens work by including active ingredients that remain on the surface of the skin that absorb, scatter, or reflect the UV radiation before it reaches the skin.
Sunscreens: How to Read a Label, Expert Tips etc.
The term, “sunless tanners” (also known as self-tanning, or UV-free tanning) refers to products that are applied to the skin to produce an effect similar in appearance to a traditional suntan without exposure to UV light. Achieving a sunless tanned appearance can be accomplished in a number of ways.