Wheels

Wheels are a simple machine to get less friction. They come in all sizes, big and small. Wheels first appeared more than 5,000 years ago in the city of Mesopotamia. Mesopotamia is now known as Iraq. There are a lot of things that have wheels like roller skates, bicycles and skateboards. There are things that have wheels that are mechanically moved. They are trucks, racing cars, even planes have wheels. The wheel is a great invention that changed the world.