Editing Light switch (section)

==History, culture, examples, and style==
[[File:Light switches.jpg|thumb|left|upright|Two light switches in one box. The switch on the right is a dimmer switch. The switch box is covered by a decorative plate.]]

The first light switch employing "quick-break technology" was invented by [[John Henry Holmes]] in 1884 in the Shieldfield district of Newcastle upon Tyne.<ref>[http://www.englandsnortheast.co.uk/electric1870s.html Electric Light Years 1878-1899 - England's North East] {{webarchive|url=https://web.archive.org/web/20150520004519/http://www.englandsnortheast.co.uk/electric1870s.html |date=2015-05-20 }}</ref> The "quick-break" switch overcame the problem of a switch's contacts developing electric arcing whenever the circuit was opened or closed. Arcing would cause pitting on one contact and the build-up of residue on the other, and the switch's useful life would be diminished. Holmes' invention ensured that the contacts would separate or come together very quickly, however much or little pressure was exerted by the user on the switch actuator. The action of this "quick break" mechanism meant that there was insufficient time for an arc to form, and the switch would thus have a long working life. This "quick break" technology is still in use in almost every ordinary light switch in the world today, numbering in the billions, as well as in many other forms of electric switch.

The ''toggle light switch'' was invented in 1916 by William J. Newton.<ref name="googlepatents">{{cite patent |country=US |number=1233597 |title=Flush Switch |pubdate=Jul 17, 1917 }}</ref>

As a component of an [[electrical wiring]] or [[home wiring]] system, the installation of light switches is regulated by some authority concerned with safety and standards. In different countries the standard dimensions of the wall mounting hardware (boxes, plates, etc.) may differ. Since the face-plates used must cover this hardware, these standards determine the minimum sizes of all wall mounted equipment. Hence, the shape and size of the boxes and face-plates, as well as what is integrated, varies from country to country.

The dimensions, mechanical designs, and even the general appearance of light switches have changed slowly over time. Switches typically remain in service for many decades, often being changed only when a portion of a house is rewired. It is not unusual to see century-old light switches still in functional use. Manufacturers introduce various new forms and styles, but for the most part decoration and fashion concerns are limited to the face-plates or wall-plates. Even the "modern" dimmer switch with knob is at least forty years old, and in even the newest construction the familiar toggle and rocker switch formats predominate.

===Orientation===
The direction which represents "on" also varies by country. In the US and Canada, it is usual for the "on" position of a toggle switch to be "up", whereas in many other countries such as the UK, Ireland, and other European countries as well as India, Australia, New Zealand (Commonwealth countries), Egypt, and China it is "down". (In [[#Multiway switching|multiway switching]], the correspondence between a single switch's state and whether lights are on or off depends on the state of the other switch[es] in the circuit.)