The Cephalic Index is a measurement used to describe the shape of a person's head. It is calculated by taking the width of the head and dividing it by its length, then multiplying the result by 100. This index helps categorize head shapes into three types: dolichocephalic (long and narrow), mesocephalic (medium), and brachycephalic (short and broad). This measurement is often used in fields like anthropology, archaeology, and medicine to study human populations and their variations. It can provide insights into genetic traits, evolutionary history, and even health conditions related to head shape, such as those seen in certain genetic disorders.