Machines help us to perform daily activities in a better efficient way.
A machine can be defined as a device by which we can either overcome a large resistive force (or load) at some point by applying a small force (or effort) at a convenient point and in a desired direction or by which we can obtain a gain in speed.
The point at which energy is supplied to a machine by applying effort is called the effort point, and the point where the energy is obtained by overcoming the load is called the load point.