Okay kiddo, imagine we are going on a long ride on a wagon pulled by horses. Now, sometimes we might need to stop the wagon because maybe the horses need a rest or we need to fix something on the wagon.
To stop the wagon, someone needs to pull on this special lever called a brake. When the brake gets pulled, it makes a part of the wagon called a brake shoe press against a part of the wheel called the rim. When this happens, it creates friction which slows down the wheel and stops the wagon.
It's important to know how to stop the wagon safely so that we don't crash or hurt ourselves. That's why when we ride in a wagon, we always have someone who knows how to stop the wagon properly.
So next time we go on a wagon ride, you'll know how we can stop safely whenever we need to take a break or fix something.