There are several different types of Alternators. In the simplest of terms, the Alternator converts kinetic energy (motion) into electrical energy in the form of AC (alternating current) that is used to charge a battery. The Alternator is only able to produce a charge once the device is in motion. The Stator and the Flywheel are the two main parts that make up an Alternator. Alternators can be found on just about any electric start device. Smaller devices like lawnmowers or motorcycles, or larger ones like cars, steam turbines, and hydroelectric dams all use Alternators to create a charge while engines or turbines are running. Because most machines that use Alternators require Direct Current (DC) to power their lighting, fuel injection, etc., the Alternator will often have a rectifier which will convert the Alternating Current (AC) generated by the Alternator to Direct Current (DC).