Magic smoke 707347 215903480 2008-05-30T05:35:34Z Slashme 451287 [[WP:UNDO|Undid]] revision 215867996 by [[Special:Contributions/59.167.188.59|59.167.188.59]] ([[User talk:59.167.188.59|talk]]): Non-notable quote, doesn't add much. [[Image:magic_smoke.jpg|thumb|200px|Smoke released from an electronic component]] [[Image:No_blue_smoke.jpg|thumb|200px|A [[computer chip]] rendered useless after overheating.]] '''Magic smoke''' (also called '''factory smoke''', '''blue smoke''', or '''magic blue smoke''') refers to smoke produced by malfunctioning electronic circuits. The origins of the magic smoke has become a [[running joke|running]] [[in-joke]] that started among [[Electrical engineering|electrical engineers]] and [[technician]]s before it was more recently adopted by computer [[computer programmer|programmers]]. The actual origin is the [[silicon]] material that are used in most common semiconductor devices such as [[transistor]]s and [[integrated circuit]]s. When it burns, it produces smoke that is blue in color. ==Joke== The magic smoke is observed to come out of electronic components when overheated, often through exposure to an extreme [[electrical current]] usually caused by the application of excess [[voltage]] through some failure of the circuit. According to the joke, at their factories, manufacturers put a little bit of [[magic (paranormal)|magic]] smoke into every electronic component and it is this smoke which makes the device work. In support of this joke, once the magic smoke has been released, the device lacks its key component and no longer works. The smoke thus can be thought of as an essential part in the device's function. It is also noted that once let out, the magic smoke can no longer be put back in. In some variations of the joke, it is alleged that the major microchip production companies (especially the large [[microprocessor]] manufacturers) are involved in a [[Conspiracy theory|conspiracy]] to keep the true nature of their products under wraps.<ref>{{citation|title=Robust Electronic Design Reference Book |author= John R. Barnes|year= 2004|publisher=Springer|url= http://books.google.com/books?id=V2GIeUAZj0kC&pg=PT308&dq=%22Magic+smoke%22&ie=ISO-8859-1&output=html&sig=mu9toNIb0nR-jUZFZn1NhWRRrPs|id=ISBN 1402077378}}</ref> ==Usage== This has led to use of the phrases (and variants of) "leaking smoke", "the magic smoke is escaping", or "you let the smoke out!" as a [[euphemism]] for the destruction of a processor, [[integrated circuit]] or other electronic component, by overheating. When a device is powered on for the first time, it is often called a "[[Smoke testing#Testing in electronics and electrical engineering|smoke test]]". ==References== {{Reflist}} ==External links== * [http://catb.org/~esr/jargon/html/M/magic-smoke.html ''Magic smoke''] entry in the [[Jargon File]] * [http://wombat.doc.ic.ac.uk/foldoc/foldoc.cgi?magic+smoke ''Magic smoke''] entry at FOLDOC [[Category:Electronics terms]] [[Category:Electronics and society]] [[Category:In-jokes]] [[Category:Computer humor]]