Oh the great inventions of the world. But who doesn't agree that the wheel is one of the best ever? It wouldn't be the same if it was square. And for bike's it just wouldn't be the same if it was wooden. I guess along with the wheel we ought to thank the guys that perfected inflatable rubber tires, too.
Wheel
The bright idea of creating something round that could move heavy loads seemed to have dawned on several people at the same time. "First wheels" have been found that are the same age (dating back the fourth millenium BC...or Neolithic age) in various geographical locations across the world.
Tire
The idea of making a wheel out of something softer than wood, metal or stone didn't really take off until 1880's, after the many uses for vulcanized rubber were being discovered. The first guy to think about putting rubber on a tire to make the ride softer was actually looking for a better tire for a bicycle.