What does Wheel and axle do?

There are two general forms:

- a wheel attached to a fixed axle which rotates in a frame or mount

- a wheel which has a hole in its center and revolves around an axle passing through it.

In the first, lubrication can be applied to the mounting bracket where it holds the axle. In the second, lubrication is applied to the axle (shaft) where it passes through. This can also include ball bearings that distribute the weight and themselves roll within a mounting.