[header] How to use a can opener [title] Understand the components of a can opener. [step] Though it may look like a simple tool, it's actually comprised of three different machine apparatuses. The two long arms that clamp onto the side of the can are the levers. 
The handle that is used to turn the can is comprised of an axle and a wheel. Lastly, the circular wheel that cuts into a can is called a wedge.