Bacteria

Hello there. I'm a secret, invisible helper. I'm so, so tiny that you can't see me, but I am everywhere. I wiggle in the dirt to help flowers grow big and bright. I float in the water you splash in. A whole bunch of my family even lives inside your tummy right now, helping you stay strong. We are the ones who turn milk into yummy yogurt and cheese. We are super busy, but you never see us working. Do you know who I am? I am Bacteria. There are trillions of me all over the world.

For a very long, long time, nobody knew I was here. Then, one day way back in the 17th century, a man named Antonie van Leeuwenhoek built a special looking glass. It was called a microscope, and it made tiny things look big. He was very curious. He looked at a drop of water. He even looked at the gunk on his teeth. And what did he see? Me. He saw thousands of my family members wiggling and swimming around. He was the very first person to ever see me. He called us 'little animals.' It was so exciting.

Now everyone knows about us. Most of us are good bacteria, and we are here to help you and the world. But I do have some naughty cousins who can make you feel sick. They're the reason grown-ups tell you to wash your hands with soap and water before you eat. That washes the naughty ones away. But don't worry, my good-guy family is much bigger. So next time you eat a cup of yogurt, give a little wave to your tummy. You're saying hello to me, your tiny, hardworking friend.