Melanin is a pigment synthesized by melanocytes in the epidermis, primarily in response to ultraviolet (UV) radiation. The process of melanin production, known as melanogenesis, is initiated when UV exposure activates the melanocortin-1 receptor (MC1R) on melanocytes, triggering the conversion of tyrosine into melanin through the enzyme tyrosinase. This pigment acts as a natural defense mechanism by absorbing UV radiation, thereby reducing DNA damage, oxidative stress, and inflammation, which helps protect against skin cancer and photoaging. There are two main types of melanin: eumelanin, which provides brown to black pigmentation and offers stronger UV protection, and pheomelanin, responsible for yellow to red hues, which is less effective in UV protection. Melanin production also varies with genetic factors, skin type, and hormonal influences, contributing to the diversity in skin color and its varying ability to cope with UV exposure.