Motor speed controllers are electronic devices that control motor speed.

Motor controllers receive supply voltages and provide signals to motor drives that are interfaced to motors.

AC motors include single, multiphase, universal, induction, synchronous, and gear motors.

DC motors are most commonly used in variable speed and torque applications.

Stepper motors use a magnetic field to move a rotor in small angular steps or fractions of steps.

Gearmotors consist of an AC or DC motor with an integral gearbox or gear head that steps delivered speed up or down

AC motor drives interface controllers to AC motors.