AC motors also known as alternating current motor.  They include synchronous, servo, universal, inductionand single/multiphase types.  The advantage of using an AC motor compared to a DC motor would be minimized cost and they are particularly well suited for constant-speed applications. The most widely chosen AC motor would be either a synchronous or induction AC motor. 

DC motors include a variety of types such as linear, stepper, servo motor or gear motors.  They are commonly used in variable speed and torque applications and can be more costly than their counterpart AC motor.  They are found in applications such as conveyors, extruders, printing presses and packing equipment.