lever · fulcrum · pivot · leverage · rigid
A lever is a simple machine made of a rigid bar that rests on a pivot point called a fulcrum. By pushing down on one end of the bar, you can lift a heavy load on the other end. Levers give us leverage, which means we can move objects that would be impossible to lift by hand. There are three types of levers, depending on where the fulcrum is placed. Common examples of levers include scissors, pliers, a baseball bat, and a see-saw. Even the human arm is a lever — the elbow joint acts as the fulcrum.