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

The primary difference is size and application. 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 light bulbs have an integral ballast that is built into the base of the light bulb, whereas linear fluorescent tubes require a separate ballast independent of the bulb. Both types are energy efficient light sources.