Bearings - Their Use

As a kid, I saw the different sizes of bearings my father has in this plastic container. He does not actually collect bearings. He just keeps them for immediate purposes. So, on what objects are bearings being use?

• roller skates
• electric motor
• lazy susan turn table

There are so many uses of bearings. They say even a hard disk has a bearing. That I still have to research.

Bearings - Their Use