Nails themselves are made of keratin (say: KAIR-uh-tin).

You may not think about your nails, unless you just painted them blue or your mom says it's time to trim them. But your nails have a job to do. The hard surface of your nails helps to protect the tips of your fingers and toes. And your fingernails make it easier to scratch an itch or remove a dog hair from your sweater.