Refers to according to the law of electromagnetic induction motor to realize electrical energy conversion or transfer of an electromagnetic device, or convert one form of energy into another form of energy.

Motor converts electrical energy into mechanical energy (commonly known as the motor), the generator converts mechanical energy to electrical energy. Motor in a circuit with the letter "M" (with the old standard

"D"). Its main function is to produce drive torque, as with all electrical appliances or mechanical power.