Wheels... Rims... What's the Difference?

Rims are the outer "rim" of the wheel. Rims are like a donut or a ring (they look like a giant wedding band). That is what a "rim" is..."the border edge of something".

Now if you take a "CENTER" (it looks like a dinner plate with holes in it) and put it inside the rim, VOILA! You have a wheel.

Just as 2 plus 2 equals 4...
"CENTER" plus "RIM" equals "WHEEL".

You need both rims and a center to make a wheel. The TIRE on the other hand is the part made of rubber.