Hair is categorized by hair type, hair texture and shape. What is known in the industry as "Hair Type" 1, 2a, 2b, 2c, 3a, 3b, 3c, 4a, 4b, 4c, should really be called hair shape. HAIR TYPE Normal Hair Normal Hair has balanced sebum; it is not too oily and not too dry. The hair has shine, sheen and vibrancy to it. Dry Hair Dry hair lacks sebum.