What Is A Simple Machine?

A simple machine is a machine devoid of moving parts and that which requires a lone force to work. The inventory of simple machines consists of: the pulley, the single wedge and double wedge, the lever, the screw, the inclined plane (a familiar inclined plane is a ramp) and the wheel and axle. The simple machine falls into two diverse categories: those reliant on the vector resolution forces, i.e. (the screw, the inclined plane and the wedge) and the other dependent on symmetry of torques i.e. (the wheel, lever and the pulley).
Two or more simple machines placed as one form a compound machine. The machines used on a large scale at present are compound machines. The simple machines are also well known as 'the machines of Leonardo times'.