The Electric light reference article from the English Wikipedia on 24-Jul-2004 (provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Electric light

Most of the industrialized world is lit by electric lights, which are used both at night and to provide additional light during the daytime. These lights are normally powered by the electric grid, but some run on local generators, and emergency generators serve as backups in hospitals and other locations where a loss of power could be catastrophic. Battery-powered lights, usually called "flashlights" or "torches", are used for portability and as backups when the main lights fail.

Types of electric lighting include:

• incandescent light bulbs
• arc lamps
• gas-discharge tubes, e.g., fluorescent lights, neon lamps, modern photographic flashes
• lasers
• light-emitting diodes, including OLEDs

The total amount of artificial light is sufficient for cities to be easily visible at night from the air, and from space. This wasted light should not be confused with the light pollution that burdens astronomers and others, although it is the source of it.
Human-made lights highlight particularly developed or populated areas of the Earth's surface, including the seaboards of Europe, the eastern United States, and Japan.

---

This article is a stub. You can help Wikipedia by expanding it.

This is the "Electric light" reference article from the English Wikipedia. All text is available under the terms of the GNU Free Documentation License. See also our Disclaimer.