Melanins are pigments produced by melanocytes in the skin, hair, and eyes. Synonyms for melanins include pigments, colorings, dyes, chromophores, and coloring agents. These compounds give color to numerous organisms and can vary in shade, from yellow-orange to brown-black. In animals, melanins act as a protective shield against the harmful effects of ultraviolet radiation. In humans, they determine skin color and protect the skin from sunburn. Because of its importance in various biological processes, melanins have been used in the development of novel therapies for diseases such as cancer and Parkinson's.