Our skin is made of skin cells that are called fibroblasts. They're sort of flat, and they lie in layers. The top layer of skin cells dies and new layers grow at the bottom of our skin, inside our bodies.

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Skin is made of a protein called keratin. It's the same stuff that hair, fingernails, reptile scales, and bird feathers are made of.

Our skin is made up of tiny units of life called cells! Cells make up everything in our bodies from our bones to our blood to our skin. There are different kinds of cells for different parts of the body. Our skin is actually made up of many layers of different kinds of cells! The top layer is called the epidermis. The epidermis protects our organs and muscles and skeleton from the outside world and infections. There are many different sublayers of the epidermis, but I won’t get into that here. The next layer down is called the dermis. The dermis contains what is called “connective tissue” - basically groups of cells that connects things. It contains nerve endings, hair follicles, sweat glands, blood vessels, among other things (and all of these things are also made up of different types of cells). Beneath the dermis is subcutaneous tissue, which connects skin to the muscle and bone underneath it. The human body is an amazingly complex system! Something as simple as skin has many parts that make it up which allow us to live our every day lives.