A simple machine is a tool with few or no moving parts that makes work easier. It can let us use a smaller force, or change the direction of a force.

A lever is a bar that turns around a fixed point called the fulcrum. You push on one part (the effort) to move something on another part (the load). Seesaws, crowbars and bottle openers are levers. The further from the fulcrum you push, the less force you need.

A ramp (inclined plane) lets you lift something using a smaller force by moving it a longer distance. A wheel and axle is a wheel joined to a rod, like a doorknob or a steering wheel. A pulley is a wheel with a rope around it. It can change the direction of a pull, like on a flagpole.

Simple machines do not make work disappear. When you use less force, you usually have to move further.