- from Simple Machines
Early civilizations did fine without the wheel and axle (the rod that goes through a wheel).
The Egyptians had no wheels, yet they were able to build the pyramids. The Aztecs created sophisticated cities with many buildings, roads, and temples—all without wheeled vehicles.
But we’ve come a long way since then, and wheels helped get us here. Wheels cut down on friction—in this case, the resistance between what you are trying to move and the surface you are pulling against. Imagine trying to pull a child in a red wagon that has no wheels on it. It would be hard—if not impossible—because of the amount of friction between the sidewalk and the wagon. But put wheels and axles on the wagon, and you can easily move the wagon and child along.