They hold light bulbs and make electrical contact to provide a bulb with power. Lamp holders are used with most light sources for incandescent, fluorescent, and compact fluorescent lamps (CFL).A Lamp / Bulb Holder is an electrical device that securely holds and provides power to a light bulb. It also offers the convenience and comfort of replacing bulbs easily when needed. Lamp holders are mechanical devices that support lamps and connect them to electrical circuits.