Hair is made of a substance called keratin. This is the same material that makes up your fingernails. Hair grows out of the skin. The part of the hair under the surface is alive. Each hair sits in a little hole called a follicle.
Follicles also have glands that help coat your hair with oil. Your hair and fingernails are made of the same stuff. The hair above the surface of the scalp is called the shaft. This part of the hair is not alive. That’s why it doesn’t hurt when you cut it.
Each shaft of hair has a layer of armor called a cuticle to protect it. If your hair is too dry, the cuticle can break and your hair can look dull. Hair gets its coloring from a substance called melanin. Hair with more melanin is dark, and hair with less melanin is light.