Archimedes invented the pulley.Pulleys are used to lift loads,apply forces and to transmit power.
Pulleys are assembled to form a block and tackle in order to provide mechanical advantage
to apply large forces. The purpose of the pulley is to move heavy loads with less effort.A pulley is made out of rope or belt that is wrapped around wheels. The more pulleys that are used, the less effort is needed to lift the objects.The rope is pulled from one end and makes it way through the pulley,while the object is lifted on the other end.