What's the difference between a compact fluorescent light bulb and a fluorescent bulb?

"The primary differences are in size, shape and energy usage; compact fluorescent bulbs are made in special shapes (which require special technologies) to fit in standard household light sockets, like table lamps and ceiling fixtures. In addition, most compact fluorescent lamps have an "integral" ballast that is built into the light bulb, whereas most fluorescent tubes require a separate ballast independent of the bulb. Both types offer energy-efficient light. " 1

"A ballast is used to stabilize the current flow in lamps. Ballasts vary greatly in complexity. They can be as simple as a series resistor as commonly used with small neon lamps. For higher-power installations, too much energy would be wasted in a resistive ballast, so alternatives are used that depend upon the reactance of inductors, capacitors, or both. Finally, ballasts can be as complex as the computerized, remote-controlled electronic ballasts used with fluorescent lamps."2


1http://www.gelighting.com/na/home_lighting/ask_us/faq_compact.htm#breaks
2 http://en.wikipedia.org/wiki/Electrical_ballast

Jill Robinson