For thousands of years, people looked up at clouds with a lot of wonder. What are they? What’s inside them? You might see, on TV, images of people rolling around on clouds like they are fluffy pillows. You might play a video game where a character jumps from cloud to cloud. You might read Jack and the Beanstalk, and imagine a whole kingdom existing up on top of a cloud.
Only recently have people been able to fly up and through the clouds to know for certain what’s inside. Clouds are the same on the inside as they are on the outside! They’re made of tiny drops of water that are so light they can float on air. When they grow to be heavy enough, they will fall as rain, but until then, the whole cloud is made of these very tiny water drops.
If you ever take a plane ride and go through a cloud, it will look just like you’re traveling through a thick fog. Fog is pretty much a cloud, just really close to the ground!