You would probably be quick to agree that moving a heavy item is easier with a wheelbarrow than if you had to carry the item yourself. A skateboard probably can get you around easier than walking (at least, if you’re skilled with a skateboard!). Maybe you prefer to ride a bike or take a train? All of these machines use the same simple machine, the wheel and the axle, to make your work easier.
Wheels and axles have a mechanical advantage just as ramps, wedges and levers do.
Wheels have been around a long time, since about 4000 BC.
The first wheel was invented by the Sumerians in Mesopotamia. It may seem like a long time ago, but humans have been around a lot longer than that, so it actually took many thousands of years for people to come up with the idea. This is probably because there were no civilizations so the wheel wasn’t necessary, and also because the idea of a wheel is actually pretty complex.
