University of Edinburgh

BSL Physics Glossary - bulb - definition

A bulb gives out (emits) light. There are different types of bulb. The filament bulb is used, for example, in a car headlight or for lighting in houses.  There are also fluorescent lights which are energy saving. Another type is an LED (light-emitting diode). These are getting more popular now. For example you can see an array of LEDs in brake lights.

incandescent                  fluorescent      LED

Incandescent (filament)     Fluorescent (energy saving)    LED lamp

(pictures from Wikimedia)