Stepper motor is a kind of electrical pulses into angular displacement of the actuator. Popular point: when the stepper driver receives a pulse signal, it is driving a stepper motor according to set the direction of a fixed Angle (and the step Angle).

You can by controlling the pulse number to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; At the same time you can control the pulse frequency to control motor rotation speed and acceleration, so as to control achieved. So when need accurate positioning or speed regulation control all can consider using a stepper motor.