The six types of simple machines are the pulley, the lever, the wedge, the wheel and axle, the inclined plane and the screw. Simple machines are designed to make work easier.
A lever consists of a bar and fulcrum. A seesaw and wheelbarrow are examples of a lever. A wheel and axle consists of a circular object attached to a bar in its center. Ferris wheels and tires are examples of a wheel and axle. An inclined plane has a slanted surface connecting a lower level to a higher level. A ramp is an example of an inclined plane. A wedge has one or more slanting sides ending in a sharp edge. Axes and knives are examples of a wedge. A screw has a shaft with an inclined groove on the surface. A pulley has a wheel with a groove on its edge.