Hair is a filamentous, usually pigmented outgrowth from the skin found on all mammals (except the lips, fingertips, palms and soles of the feet, and the glans penis). It is composed of non-living cells called keratin. It serves many functions, including protecting the scalp from sunlight, helping to regulate body temperature, and contributing to personal aesthetics and social identity. It also helps to protect sensitive areas such as the eyes from dust and other microbes.
The follicle of each hair is located in the lower dermis layer of the skin. At the base of each follicle is an oil gland called a sebaceous (sih-BEE-oss) gland that produces lipids, or oils, that help to keep the hair and skin from becoming too dry. A strand of hair begins to grow from the bottom of each follicle at an area called the papilla, which gets its nutrients from a blood vessel that runs underneath it. As the follicle grows, the papilla is covered with new cells that form and harden, resulting in the strand-like appearance of hair. These cells then push their way out through the follicle’s surface as the hair grows, and when the hair reaches full length, they are pushed out of the follicle through the epidermis layer of the skin.
Each strand of hair is made of multi-layered, keratinized (KEHR-tin-ized) flat cells that are twisted into rope-like structures. This structure is what gives hair its strength and color, as well as its luster. The keratinized cells are embedded in an outer layer that is made of proteins, peptides and lipids. These structures are all arranged in layers, with the innermost layer being the most protein-rich, and the outermost being the least. The hair’s lustrous, reflective qualities are due to the way these layers reflect light.
In addition, the elastin in hair gives it its natural flexibility. This is why some people who have straight hair have a more difficult time keeping their hair in place, while others can effortlessly style their hair into smoky battlefield buns or other styles with little effort.
Using descriptive words to describe the way that a character’s hair looks, lays and moves will help the reader have a better understanding of that person, which will make them more interested in the story. These descriptive terms can be used in combination to describe the whole look of a character, or they can be incorporated into specific scenes to add detail and depth.
For example, a character with dyed hair may need a shampoo that is color-safe so the dye doesn’t fade between washes. Similarly, a person with damaged or brittle hair may need a more intense repair treatment. Often, these types of products will have a label on them that tells you what type of hair they are describing, for example: “Straight”, “Wavy”, or “Curly”. A writer can use this information to determine which specific product will work best for the character’s hair. This will ensure that the characterization of their hair is as accurate as possible.