The more you know about your hair, the better you can care for it! Your hair has two separate parts: the root and the shaft. The root is the part of the hair located just under the skin surface. The hair follicle houses the entire hair root. The papilla is where all of the action takes place; it is a rich blood and nerve supply that nourishes the hair shaft and produces hair cells. The bulb is a white sack located on the lower part of the hair that covers the papilla.

The hair shaft is what is grows out of the hair follicle and is what we consider to be hair. It has three parts; the cuticle, cortex and medulla.

The outer layer of your hair shaft is called the cuticle, which holds your hair together. The cells or scales that make up the cuticle layer overlap similarly to the scales on a fish or the shingles on a roof. In healthy hair, the cuticle scales lay flat. In damaged hair, the scales may be missing or broken. (

Chemical straighteners must penetrate through the cuticle to access the cortex, where shape and color changes take place.

Hair is made of dead keratin (protein) cells that are pushed up through the scalp at an average rate of about one-half inch per month for six inches of hair growth each year.

Keep your hair healthy by eating well, frequent conditioning and gentle treatment.

Nicole Elizabeth Smith, the author of "Healthy Black Hair" (2003), is a freelance health and beauty writer and a graduate of Michigan State University. She and her son Zack live in Michigan. Currently, she is beauty editor for www.myhairbook.com.

nicole@myhairbook.com