Hair color is provided by pigments produced by cells called:"melanocytes" The pigments are called "melanin". Melanin is found intwo forms: Eumelanin is the dark pigment which predominates in blackhair and Pheomelanin is a lighter pigment, which is found in red andblond hair.In humans, melanocyte cells are found diffusely scattered in the skin andalso in little clusters in the hair follicles.There are many factors affecting hair color e.g.: stem cell, aging,chemical, environment, weathering, and nutritional factors etc …..The most common disorders of pigmentation of the hair are prematuregraying hair (canities), poliosis, green hair, blue hair and yellow hair.Decreased hair pigmentation in which dark hair appears lighter may occurin the following condition: Waardenburg's syndrome, piebaldism ,Albinism , Hutchinson-Gilford progeria type syndromes and Werner'ssyndrome