Your Skin is the largest organ of your Body. No matter what you think of it, your skin is very important. It covers and protects everything inside your body. Without your skin, your muscles, bones, and organs would be hanging out all over the place. The Skin holds everything together. It also:

• protects your body
• helps keep your body at just the right temperature
• allows you to have the sense of touch.

Your Skin consists of three layers, the Epidermis, Dermis and Subcutaneous Fat

The Epidermis
The Epidermis is the part of your skin you can see.

Look down at your hands for a minute. Even though you can't see anything happening, your Epidermis is hard at work. At the bottom of the Epidermis, new skin cells are forming.

When the cells are ready, they start moving toward the top of your Epidermis. This trip takes about 2 weeks to a month. As newer cells continue to move up, older cells near the top die and rise to the surface of your skin. What you see on your hands (and everywhere else on your body) are really dead skin cells.

These old cells are tough and strong, just right for covering your body and protecting it. But they only stick around for a little while. Soon, they'll flake off. Though you can't see it happening, every minute of the day you lose about 30,000 to 40,000 dead skin cells off the surface of your skin.

So just in the time it took you to read this far, you've probably lost about 40,000 cells. That's almost 9 pounds (4 kilograms) of cells every year! But don't think your skin might wear out someday. Your epidermis is always making new skin cells that rise to the top to replace the old ones. Most of the cells in your epidermis (95%) work to make new skin cells.

And what about the other 5%? They make a substance called melanin. Melanin gives your skin its color. The darker your skin is, the more melanin you have. When you go out into the sun, these cells make extra melanin to protect you from getting burned by the sun's ultraviolet, or UV rays.

That's why your skin gets tan if you spend a lot of time in the sun. But even though melanin is mighty, it can't shield you all by itself. You'll want to wear sunscreen and protective clothing, such as a hat, to prevent painful sunburn. Protecting your skin now also can help prevent skin cancer when you get older.

The Dermis
The next layer down is the Dermis. You can't see your Dermis because it's hidden under your Epidermis. The Dermis contains nerve endings, blood vessels, oil glands, and sweat glands. It also contains collagen and elastin, which are tough and stretchy.

The nerve endings in your Dermis tell you how things feel when you touch them. They work with your brain and nervous system, so that your brain gets the message about what you're touching. Is it the soft fur of a cat or the rough surface of your Skateboard?

Sometimes what you feel is dangerous, so the nerve endings work with your muscles to keep you from getting hurt. If you touch something hot, the nerve endings in your Dermis respond right away: "Ouch! That's hot!" The nerves quickly send this message to the brain or spinal cord, which then immediately commands the muscles to take your hand away. This all happens in a split second, without you ever thinking about it.

Your Dermis is also full of tiny blood vessels. These keep your skin cells healthy by bringing them the oxygen and nutrients they need and by taking away waste. These blood vessels are hard to see when you are young but become more visible as you get older. In short, as the Dermis gets older, it gets thinner and easier to see through.

The Dermis is home to the oil glands, too. These are also called sebaceous glands and they are always producing sebum. Sebum is your skin's own natural oil. It rises to the surface of your epidermis to keep your skin lubricated and protected. It also makes your skin waterproof - as long as sebum's on the scene, your skin won't absorb water and get soggy.

You also have sweat glands on your epidermis. Even though you can't feel it, you actually sweat a tiny bit all the time. The sweat comes up through pores, tiny holes in the skin that allow it to escape. When the sebum meets the sweat, they form a protective film that's a bit sticky.

The Third Layer Is Subcutaneous Fat
This third and bottom layer of your skin is called the subcutaneous layer. It is made mostly of fat and helps your body stay warm and absorb shocks, like if you bang into something or fall down. The subcutaneous layer also helps hold your skin to all the tissues underneath it.

This layer is where you'll find the start of hair, too. Each hair on your body grows out of a tiny tube in the skin called a follicle. Every follicle has its roots way down in the subcutaneous layer and continues up through the Dermi.