Hair color refers to the pigmentation of hair follicles, which can vary widely among individuals. The primary types of hair colors include black, brown, blonde, and red. These colors are determined by the amount and type of melanin present in the hair. For example, eumelanin contributes to darker shades, while pheomelanin is responsible for lighter and red hues. In addition to natural hair colors, people often choose to dye their hair for various reasons, including fashion or self-expression. Hair dye can come in a variety of shades and can be temporary or permanent. Popular trends include ombre and balayage, which create unique color effects.