Hair is structured formations from keratin, which grow on human skin. They perform several functions, including: Protection - hair protect the skin from the sun, wind and other elements. Thermal insulation - hair helps to retain heat in the body. Sensation of touch - hair helps us to feel touching the skin. Image - hair can be used to create various styles and images. Hair structure The hair consists of three layers: The cuticle is an outer layer of hair that protects it from damage. Cortex i...