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Flashlight
A flashlight, or torch (as it is known in the United Kingdom), is a handheld portable electric spotlight[?]. A typical flashlight consists of a small electric lightbulb with associated parabolic reflector, powered by electric batteries, and with an electric power switch. The components are mounted in a housing that contains the necessary electric circuit and provides ease of handling, a means of access to the batteries for replacement, and a clear covering over the lightbulb for it's protection.
Although a relatively simple device, its invention did not occur until the late 19th century because it depended upon the earlier invention of the electric battery and electric light. The batteries in the first ones were of such short useful life that the common method of operating them was to flash them just long enough to discern the environs, and only as needed; hence the term "flash-light".
Recently, flashlights which use LED's instead of conventional lightbulbs have become available. LED's are far more efficient than, and use less power than normal lightbulbs, and so torches which use them have longer battery lifetimes.
Hobbyists who enjoy modifying and collecting flashlights enjoy a popular forum at http://www.candlepowerforums.com
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