Human hair is unique and surprisingly complex. Many factors determine how hair grows, its texture, and its color. Humans are distinct from other mammals in that hair has become a largely cosmetic feature rather than a necessity. However, some areas of hair on the human body still provide protection. In addition, the body possesses different types of hair, each with different cellular construction that provides unique characteristics and functions.


1. Hair Structure

What most people refer to as “hair” is two distinct structures: the hair follicle and the hair shaft. The hair follicle sits in the dermis layer of the skin and manages stem cells. These assist with regrowing hair and also healing skin after an injury. The hair shaft is the section that is normally visible. It consists of three layers: the cuticle, the cortex, and the medulla.

hair structure ericsphotography / Getty Images


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