The document defines and provides examples of 6 simple machines: lever, pulley, wheel and axle, wedge, screw, and inclined plane. It then discusses each machine in more detail, defining them and providing their mechanical advantages. Specifically, it explains that the mechanical advantage of an inclined plane is the length of the slope divided by the height. For a screw, it is the circumference divided by the pitch. For a wedge and lever, it depends on the length of the effort/load side relative to the fulcrum. Pulleys can provide advantage through fixed, movable, or combined systems. The wheel and axle advantage comes from the radius ratio. Rube Goldberg machines combine multiple simple machines.