The study of Anthropometrics (human measurement) is concerned with the physical sizes and shapes of humans.  Of particular interest are the differences between and among different populations (men vs. women, Northern Europeans vs. Japanese).

Anthropometric Variance Parameters

Gender height, size, weight, strength, and body segment proportion	Age height, size, weight, strength, and body segment proportion	Ethnicity height, size, weight, and body segment proportion

Anthropometrics literally means man (anthro) measurements (metric).  It is the measurement of the size and proportions of the human body, as well as parameters such as reach and visual range capabilities.  Accurate data on height, weight, limb, and body segment sizes are needed to design items ranging from clothing, furniture, automobiles, buses, and subway cars to space shuttles and space stations.  Anthropometrics enables us to properly size items, including system interfaces, to "fit" the user.