What’s the difference between alternator and generator?

The main difference between an alternator and a generator is how they produce electricity and their working structure.

An alternator only generates alternating current (AC) first, then uses a rectifier to convert it to DC. It has a rotating magnetic rotor and a stationary stator coil. Alternators are lightweight, highly efficient, more durable, and widely used in cars, trucks, and machinery to charge batteries and supply vehicle power.

A traditional generator produces direct current (DC) directly or outputs AC mechanically. It uses a stationary magnetic field and rotating armature coils. Generators are bulkier, lower in efficiency, and mostly used for large power supply units, industrial power generation, and emergency standby power.