Hair color refers to the pigmentation of hair follicles, which can vary widely among individuals. The most common natural 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, black hair has a high concentration of eumelanin, while blonde hair has less. In addition to natural colors, people often choose to dye their hair for various reasons, leading to a vast array of shades and styles. Hair dye can create vibrant colors like blue, pink, or purple, allowing for personal expression. The choice of hair color can reflect individual personality, cultural influences, or current fashion trends.