Light bulb joke: an endless-variations joke
Light bulb jokes are very populair. Wikipedia has a specific section on light bulb jokes!
The lightbulb joke is an example of an endless-variations joke and has possibly thousands of versions covering every imaginable culture, belief, occupation and special-interest group.
For example, hundreds of jokes about light bulbs can be found at the website of Thad. The last link of jokes about light bulbs has been inspired on this website.
More information about the light bulb
The incandescent light bulbs are also called electric lamps or light globes. The light bulb is a source of artificial light that works by incandescence.
An electric current passes through a thin filament, heating it and causing it to emit light.
The enclosing glass bulb prevents the oxygen in air from reaching the hot filament, which would be otherwise rapidly destroyed by oxidation.
The light bulbs will eventaully disapear. Because these lamps have a relatively poor luminous efficacy, they are gradually being replaced in many applications by fluorescent lights, high-intensity discharge lamps, LEDs, and other devices.