Simple machine

A simple machine is any device that only requires the application of a single force to work.

The traditional list of simple machines is:

• The [inclined plane]?
• The screw?
• The wedge?
• The lever?
• The wheel
• The pulley

All of these convert low forces into high forces or vice versa, and the ratio of the input force to the output force is the Mechanical advantage. The archimedes screw?, which is a pump, is an example of a complex machine where the screw is a helical inclined plane.

There's also a record label named Simple Machines: http://www.simplemachines.net