What is known as control transformer?

THIS IS ONLY DESCRIPTIVE NAME - THE TRANSFORMER USED IN CONTROL PANELS ARE USED FOR STEPPING DOWN TO A LOWER AND SAFER VOLTAGE HANDLING BY TECHNICIANS - 220V,110V, 48V, 24V, 12V, 6V. USUALLY FOR THE COILS OF CONTACTORS, RELAYS, TIMERS, PROTECTIVE DEVICES, PILOT LAMPS, METERINGS.