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{{Redirect3|$|For the unit of currency, see [[Dollar]] or [[Peso]]. For other uses, see [[$ (disambiguation)]]}}
{{Technical reasons|$#*! My Dad Says|the television show|$h*! My Dad Says}}

{{Punctuation marks|$}}
The '''dollar''' or '''peso sign''' ('''$''') is a symbol primarily used to indicate the various  [[peso]] and [[dollar]] units of [[currency]] around the world.

== Origin ==
[[File:Dollar Symbol Evolution.svg|thumb|left|150px|alt=Dollar symbol evolution]]

The sign is first attested in [[United Kingdom|British]], [[United States|American]], [[Canada under British rule (1763–1867)|Canadian]], [[New Spain|Mexican]] and other [[Hispanic America|Spanish American]] business correspondence in the 1770s, referring to the [[Spanish colonization of the Americas|Spanish American]] [[peso]],<ref>Lawrence Kinnaird (July 1976). [http://links.jstor.org/sici?sici=0043-3810%28197607%297%3A3%3C253%3ATWFOR%3E2.0.CO%3B2-4 "The Western Fringe of Revolution,"] ''[[The Western Historical Quarterly]]'' '''7(3)''', 259.</ref><ref>{{citation | journal = [[Popular Science]] | title = Origin of Dollar Sign is Traced to Mexico | year = 1930 | volume = 116 | issue = 2 | issn = 0161-7370 | page = 59 | url = http://books.google.com/books?id=4ykDAAAAMBAJ&printsec=frontcover#PPA59,M1}}</ref> also known as "[[Spanish dollar]]" or "piece of eight" in British North America, which provided the model for the [[United States dollar|currency]] that the United States later adopted in 1785 and the larger coins of the new Spanish American republics such as the [[Mexican peso]], Peruvian eight-[[Peruvian real|real]] and Bolivian eight-[[Bolivian sol|sol]] coins.

The best documented explanation reveals that the sign evolved out of the Spanish and Spanish American [[scribal abbreviation]] "p<sup>s</sup>" for pesos. A study of late eighteenth- and early nineteenth-century manuscripts shows that the ''s'' gradually came to be written over the ''p'' developing a close equivalent to the "$" mark.<ref>[[Florian Cajori]] ([1929]1993). ''[http://books.google.com/books?id=7juWmvQSTvwC&pg=RA1-PA22&dq=isbn:0486677664#PRA1-PA22,M1 A History of Mathematical Notations]'' (Vol. 2), 15-29.</ref><ref>Arthur S. Aiton and Benjamin W. Wheeler (May 1931). [http://links.jstor.org/sici?sici=0018-2168%28193105%2911%3A2%3C198%3ATFAM%3E2.0.CO%3B2-Q "The First American Mint"], ''The Hispanic American Historical Review'' '''11(2)''', 198 and note 2 on 198.</ref><ref>{{cite book | last = Nussbaum | first = Arthur | authorlink = Arthur Nussbaum | title = A History of the Dollar | publisher = Columbia University Press | date = 1957 | location = New York | page = 56 |quote= The foreign coins remained in circulation [in the United States], and the more important among them, especially the Spanish (including the Mexican) dollars, were declared by Congress on February 9, 1793, to be legal tender. The dollar sign, $, is connected with the peso, contrary to popular belief, which considers it to be an abbreviation of 'U.S.' The two parallel lines represented one of the many abbreviations of 'P,' and the 'S' indicated the plural. The abbreviation '$.' was also used for the peso, and is still used in Argentina.}}</ref><ref>Riesco Terrero, Ángel (1983). ''Diccionario de abreviaturas hispanas de los siglos XIII al XVIII: Con un apendice de expresiones y formulas juridico-diplomaticas de uso corriente''. Salamanca: Imprenta Varona, 350. ISBN 84-300-9090-8</ref><ref>{{cite web |url= http://www.moneyfactory.gov/faqlibrary.html |title= 'What is the origin of the $ sign?' in FAQ Library |author= Bureau of Engraving and Printing |accessdate=December 14, 2010}}</ref>

== Alternative hypotheses ==
{{Refimprove section|date=December 2013}}

There are a number of other theories about the origin of the symbol, some with a measure of academic acceptance, others the symbolic equivalent of [[false etymologies]].<ref>F. Cajori discusses the origins of the slash-8, the Potosi mint mark, the Pillars of Hercules, the "U.S.", the Roman sestertius, and the Boaz and Jachin theories and discounts them in ''A History of Mathematical Notations'' (Vol. 2), 15-20.</ref>

=== Drawn with one vertical line ($) ===

==== Slash 8 ====
One theory is that the dollar sign is derived from a slash through the numeral eight, denoting pieces of eight. The ''Oxford English Dictionary'' before 1963 held that this was the most probable explanation, though later editions have placed it in doubt.{{fact|date=December 2013}}

==== Spanish pieces of eight ====
[[File:Potosi Real.jpg|thumb|left|Image of a 1768 Spanish Colonial Real silver coin, showing the PTSI mint mark in the lower right and left quadrants and the [[Pillars of Hercules]] surrounding a picture of the world.]]

Another theory is that the dollar sign was derived from or inspired by the [[mint mark]] on the Spanish pieces of eight that were minted in [[Potosí]] (in present day [[Bolivia]]). The mint mark, composed of the letters "PTSI" superimposed, bears a strong resemblance to the single-stroke dollar sign (see photo).  The mark, which appeared on silver coins minted from 1573 to 1825 in Potosí, the largest [[Mint (coin)|mint]] during the colonial period, would have been widely recognized throughout the North American colonies.{{Citation needed|date=September 2009}}

Alternatively, the $ symbol derives from the scroll on the pillar, on the reverse of the "pillar dollar" variety of pieces of eight.{{fact|date=December 2013}}

==== Greek mythology ====
Another theory is that the dollar sign may have also originated from [[Hermes]], the [[Greek mythology|Greek god]] of bankers, thieves, messengers, and tricksters.  One of his symbols was the [[caduceus]], a staff from which ribbons or snakes dangled in a sinuous curve.{{fact|date=December 2013}}

=== Drawn with two vertical lines ===
{{see also|Cifrão}}

The dollar sign drawn with two vertical lines is said to come from the [[Coat of arms of Spain|Spanish coat of arms]] which showed the [[Pillars of Hercules]] with a banner curling between them(see below).

====Spanish coat of arms====
[[File:Columnas Plus Ultra.png|thumb|200px|left| The [[Pillars of Hercules]] with a small "S" shaped ribbon around in the City of [[Seville]], Spain (16th Century).]]

A common theory holds that it derives from the Spanish coat of arms engraved on the colonial silver coins, the [[Spanish colonial real|reals]], (among them the Spanish dollar) that were in circulation in Spain's colonies in America and Asia. Reals and Spanish dollars were also legal tender in the English colonies in North America, which later became part of the United States and Canada.

In 1492, [[Ferdinand II of Aragon]] adopted the symbol of the Pillars of Hercules and added the Latin warning ''Non plus ultra'' meaning meaning "nothing further beyond", indicating "this is the end of the (known) world." But when Christopher Columbus came to America, the legend was changed to ''[[Plus ultra (motto)|Plus ultra]]'': meaning "further beyond."

[[File:Escudo de España (mazonado).svg|thumb|200px|left|[[Coat of arms of Spain|Spain's coat of arms]]]]

The symbol was adopted by [[Charles V, Holy Roman Emperor|Charles V]] and was part of his coat of arms representing Spain's American possessions. The symbol was later stamped on coins minted in gold and silver. These coins, depicting the Pillars of Hercules over two hemispheres and a small "S"-shaped ribbon around each, were spread throughout America, Europe and Asia. For the sake of simplicity, traders wrote signs that, instead of saying dollar or peso, had this symbol made by hand, and this in turn evolved into a simple S with two vertical bars.

==== From "U.S." ====
A dollar sign with two vertical lines could have started off as a [[monogram]] of 'USA', used on money bags issued by the [[United States Mint]]. The letters U and S superimposed resemble the historical double-stroke dollar sign [[File:Cifrão symbol.svg|19px]]: the bottom of the 'U' disappears into the bottom curve of the 'S', leaving two vertical lines. It is postulated from the papers of Dr. James Alton James, a professor of history at Northwestern University from 1897-1935, that the symbol with two strokes was an adapted design of the patriot Oliver Pollock in 1778.<ref>{{cite book | last = James | first = James Alton | title = Oliver Pollock: The Life and Times of an Unknown Patriot | publisher = Books for Libraries Press | year = 1970 | origyear = 1937 | location = Freeport | page = 356 | url = http://books.google.com/books?id=kht_DEllNccC | isbn = 978-0-8369-5527-9}}</ref>  Oliver Pollock was such a zealous patriot – known as the "Financier of the Revolution in the West" – that conjecture does not overstep its bounds in purporting this theory as viable.<ref>{{cite article | last = James | first = James Alton | title = 'Oliver Pollock, Financier of the Revolution in the West'. | publisher = The Mississippi Valley Historical Review | year = 1929}}</ref>

This theory is referred to by the character [[List_of_Atlas_Shrugged_characters#Secondary_characters|Owen Kellogg]] in [[Ayn Rand]]'s novel ''[[Atlas Shrugged]]''.{{fact|date=December 2013}}

==== "Unit of silver" ====
Another theory is that it derives from "unit of silver", each unit being one "bit" of the "pieces of eight". Before the American Revolution, prices were often quoted in units of the Spanish dollar. According to this theory, when a price was quoted the capital 'S' was used to indicate silver with a capital 'U' written on top to indicate units. Eventually the capital 'U' was replaced by double vertical hash marks.{{Citation needed|date=July 2010}}

==== German thaler ====
Another hypothesis is that it derives from the symbol used on a German [[Thaler]]. According to Ovason (2004), on one type of thaler one side showed the crucified [[Christ]] while the other showed a [[Snake|serpent]] hanging from a [[cross]], the letters NU near the serpent's head, and on the other side of the cross the number 21. This refers to the [[Bible]], [[Book of Numbers|Numbers]], Chapter 21 (see [[Nehushtan]]).{{fact|date=December 2013}}

==== Roman sestertius ====
There is a theory that the dollar sign goes back to the most important Roman coin, the [[sestertius]], which had the letters 'HS' as its currency sign. When superimposed these letters form a dollar sign with two vertical strokes (the horizontal line of the 'H' merging into the 'S').{{fact|date=December 2013}}

== Later history ==
[[Robert Morris (financier)|Robert Morris]] was the first to use that symbol in official documents and in official communications with [[Oliver Pollock]]. The US Dollar was directly based on the [[Spanish Dollar|Spanish Milled Dollar]] when, in the [[Coinage Act of 1792]], the first Mint Act, its value was "fixed" (per the [[U.S. Constitution]], Article I, Section 8, clause 1 power of the [[United States Congress]] "To coin Money, regulate the Value thereof, and of foreign Coin, and fix the Standard of Weights and Measures") as being "of the value of a Spanish milled dollar as the same is now current, and to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure, or four hundred and sixteen grains of standard silver."

According to a plaque in [[St Andrews]], [[Scotland]], the dollar sign was first cast into type at a foundry in [[Philadelphia]], [[United States]] in 1797 by the Scottish immigrant John Baine.
[[File:Bailie bell plaque.jpg|thumb|right|The plaque in St. Andrews.]]

The dollar sign did not appear on [[Coins of the United States dollar|U.S. coinage]] until February 2007,{{Citation needed|date=July 2009}} when it was used on the reverse of a $1 coin authorized by the [[Presidential $1 Coin Act of 2005]].<ref>Pub. L. No. 109-145, 119 Stat. 2664 (Dec. 22, 2005).</ref>

The dollar sign appears as early as 1847 on the $100 Mexican War notes and the reverse of the 1869 $1000 United States note.<ref>Cuhaj, p. 100, 321-22</ref><ref>{{cite web|url=http://en.wikipedia.org/wiki/Large_denominations_of_United_States_currency#.241.2C000_bill|publisher=Wikipedia|accessdate=24 October 2012|title=Large denominations of United States currency - $1,000 bill}}</ref>  The dollar sign also appears on the reverse of the 1934 $100,000<ref>{{cite web|url=http://en.wikipedia.org/wiki/Large_denominations_of_United_States_currency#.24100.2C000_bill|publisher=Wikipedia|accessdate=24 October 2012|title=Large denominations of United States currency - $100,000 bill}}</ref>  note as well as the reverse of the 1917 $1 note.{{Citation needed|date=December 2009}}

== Use in computer software ==

As the dollar sign is one of the few symbols that is, on one hand, almost universally present in computer [[character set]]s, but, on the other hand, rarely needed in their literal meaning within computer [[software]], the $ character has been used on computers for many purposes unrelated to money.<ref name="Dollar Sign ($)">{{cite web|url=http://www.scribd.com/doc/6759703/Dollar-Sign-|title=Dollar Sign ($)|format=PDF|accessdate=2010-03-28}} (Note: this paper essentially reproduces an [http://en.wikipedia.org/w/index.php?title=Dollar_sign&oldid=245019164 older version] of this Wikipedia article.)</ref> Its uses in [[programming language]]s have often influenced or provoked its uses in [[operating system]]s, and [[application software|applications]].

===Encoding===

The dollar sign "$" has Unicode code point U+0024 (inherited from Latin-1).

*{{unichar
| 0024
| Dollar sign
| ulink =
| image =
| cwith =
| size  =
| html  =
}}
*{{unichar
| FF04
| [[Halfwidth and fullwidth forms|Full-width]] Dollar sign
| ulink =
| image =
| cwith =
| size  =
| html  =
}}

There are no separate characters for one and two line variants. This is font dependent.

===Programming languages===

* $ was used for defining [[string (computer science)|string]] [[BASIC#Data types and variables|variables]] in older versions of the [[BASIC]] language ("$" was often pronounced "string" instead of "dollar" in this use).<ref name="Dollar Sign ($)"/>
* $ is used for defining hexadecimal constants in [[Pascal (programming language)|Pascal]]-like languages such as [[Object Pascal|Delphi]], and in some variants of [[assembly language]].<ref name="Dollar Sign ($)"/>
* $ is used at the starts of names to define [[variable (mathematics)|variables]] in the [[PHP]] language and the [[AutoIt]] automation script language, [[scalar (computing)|scalar]] variables in the [[Perl]] language (see [[sigil (computer programming)]]), and global variables in the [[Ruby (programming language)|Ruby]] language.<ref name="Dollar Sign ($)"/>  In Perl programming this includes scalar elements of [[Array data structure|arrays]] ''$array[7]'' and [[Hash_table#Associative_arrays|hashes]] ''$hash{foo}''.
* In most [[shell script]]ing languages, $ is used for interpolating [[environment variable]]s, special variables, arithmetic computations and special characters, and for performing translation of localised strings.<ref name="Dollar Sign ($)"/>
* $ is used in the [[ALGOL 68]] language to delimit [[ALGOL 68#formatted transput|transput format]] regions.
* $ is used in the [[TeX]] [[typesetting]] language to delimit mathematical regions.<ref name="Dollar Sign ($)"/>
* In many versions of [[FORTRAN 66]], $ could be used as an alternative to a quotation mark for delimiting strings.<ref name="Dollar Sign ($)"/>
* In [[PL/M]], $ can be used to put a visible separation between syllables of identifiers. For example, 'Some$Name' refers to the same thing as 'SomeName'.<ref name="Dollar Sign ($)"/>
* In [[Haskell (programming language)|Haskell]], $ is used as a function application operator.<ref name="Dollar Sign ($)"/>
* In several [[JavaScript]] frameworks starting with [[Prototype.js]] and also popular in [[jQuery]], $ is a common [[utility class]].
* In [[ASP.NET]], the dollar sign indicates an expression will follow it, when used in a tag in the web page. The expression that follows is .NET [[language-agnostic]]{{dn|date=November 2012}}, as it will work with c#, vb.net, or any CLR supported language.
* In [[Erlang (programming language)|Erlang]], the dollar sign precedes character literals. The dollar sign as a character can be written $$.
* In [[Cobol |COBOL]] the $ sign is used in the [[Picture clause]] to depict a floating currency symbol as the left most character. The default symbol is $ however if the CURRENCY= or CURRENCY SIGN clause is specified, any single symbol can be used.

===Operating systems===
* In [[CP/M]] and subsequently in all versions of [[DOS]] ([[86-DOS]], [[MS-DOS]], [[PC DOS]], more) and derivatives, $ is used as a string terminator (Int 21h with AH=09h).<ref name="Dollar Sign ($)"/>
*: $ is used by the <code>prompt</code> command to insert special sequences into the DOS command prompt string.<ref name="Dollar Sign ($)"/>
* In [[Microsoft Windows]], $ is used at the end of the share name to hide a shared folder. For example, \\server\share is accessible and visible through browsing, while \\server\share$ is accessible only by explicit reference. Most [[administrative share]]s are hidden.<ref name="Dollar Sign ($)"/>
* In [[Unix-like]] systems the $ is often part of the [[Command-line interface#Command prompt|command prompt]], depending on the user's [[shell (computing)|shell]] and environment settings. For example, the default environment settings for the [[bash (Unix shell)|bash]] shell specify $ as part of the command prompt.
*: The using [[history expansion]] <code>!$</code> (same as <code>!!1$</code> and <code>!-1$</code>) means the last argument of the previous command in [[bash (Unix shell)|bash]], <code>!-2$</code> expands to the last argument of the penultimate command, <code>!5$</code> expands into the last argument of the fifth command and so on. For example:
<source lang="bash">> touch my_first_file
> echo "This is my file." > !$</source>
:: where <code>!$</code> expands into <code>my_first_file</code>.
* In the [[LDAP]] directory access protocol, $ is used as a line separator in various standard entry attributes such as postalAddress.<ref name="Dollar Sign ($)"/>

===Applications===
* Formulas in [[spreadsheet]]s (e.g., [[Microsoft Excel]]) use $ to denote an absolute cell reference.<ref name="Dollar Sign ($)"/>
* $ signifies the end of a line or the file in text editors [[ed (text editor)|ed]], [[ex (text editor)|ex]], [[vi]], [[pico (text editor)|pico]] and derivatives, and, as a result:<ref name="Dollar Sign ($)"/>
* $ matches the end of a line or string in [[sed]], [[grep]], and [[POSIX]] and [[Perl]] [[regular expression]]s.<ref name="Dollar Sign ($)"/>

== Currencies that use the dollar or peso sign ==
{{Main|Dollar|Peso}}
In addition to those countries of the world that use [[Dollar#Economies which use the dollar|dollar]]s or [[Peso#Countries currently using the peso|peso]]s, a number of other countries use the $ symbol to denote their currencies, including:

* [[Nicaraguan córdoba]] (usually written as C$)
* [[Samoan tālā]] (a transliteration of the word dollar)
* [[Tongan paʻanga]]
* [[Zimbabwean dollar|Zimbabwe]] (usually written as Z$)

An exception is the [[Philippine peso]], whose sign is written as [[Philippine peso sign|₱]].

The dollar sign is also still sometimes used to represent the [[Malaysian ringgit]] (which replaced the local [[Malaya and British Borneo dollar|dollar]]), though its official use to represent the currency has been discontinued since 1993.

Some currencies use the ''[[cifrão]]'' <math>(\mathrm{S}\!\!\!\Vert )</math>, similar to the dollar sign, but always with two strokes:

* [[Brazilian real]]
* [[Cape Verde escudo]]
* [[Portuguese escudo]] (defunct)

The cifrão is also used to account for over 130,000,000 domestic standard [[U.S. Mint]] (1986+) bullion U.S. silver dollars as one dollar per one troy ounce fine (99.9%), thereby avoiding confusion with debased U.S. trade dollar-denominated tokens and [[Federal Reserve]] notes. {{Citation needed|date=December 2008}}

In Mexico and other peso-using countries, the cifrão is used as a dollar sign when a document uses pesos and dollars at the same time, to avoid confusions, but, when it used alone, usually is represented as US $ (United States dollars). Example: US $5 (five US dollars).{{Citation needed|date=February 2010}}

However, in [[Argentina]], the $ sign is always used for pesos, and if they want to indicate dollars, they always write U$S 5 or US$ 5 (5 US dollars).

In the United States, Mexico, Australia, Argentina, New Zealand, Hong Kong, Pacific Island nations, and English-speaking Canada, the dollar or peso symbol precedes the number, unlike most currency symbols. Five dollars or pesos is written and printed as $5, whereas five cents is written as 5[[¢]]. In French-speaking Canada, the dollar symbol usually appears after the number (5$), although it sometimes appears in front of it, or instead may even be totally absent.

==Other uses==

The dollar sign is also used in library cataloging to represent subsections.

Also, it is used derisively to indicate greed or excess money such as in "[[Microsoft|Micro$oft]]", "[[George Lucas|George Luca$]]", "[[Lars Ulrich|Lar$ Ulrich]]", "[[Disney|Di$ney]]", and "[[Greater Western Sydney Giants|GW$]]"; or supposed overt Americanization as in "[[British Sky Broadcasting|$ky]]". In 1872, [[Ambrose Bierce]] referred to the California Governor as [[Leland Stanford|₤eland $tanford]]. The dollar sign is also used intentionally to stylize names such as [[ASAP Rocky|A$AP Rocky]] and [[Kesha|Ke$ha]].

In [[Scrabble]] notation, a dollar sign is placed after a word to indicate that it is valid according to the [[Official Tournament and Club Word List|North American word lists]], but not according to the British word lists.<ref>{{cite web|url=http://www.tucsonscrabble.com/articles/glossary.html|title=Scrabble Glossary|publisher=Tucson Scrabble Club|accessdate=2012-02-06}}</ref>

== See also ==
* [[Euro sign]]
* [[Indian Rupee sign]]
* [[Pound sign]]
* [[Turkish lira sign]]

== Notes ==
{{reflist|2}}

==References==
{{refbegin}}
* {{cite book | author=[[Cajori, Florian]]| title=''A History of Mathematical Notations'' | location=New York | publisher=Dover (reprint) | year=1993 | isbn=0-486-67766-4}} - contains section on the history of the dollar sign, with much documentary evidence supporting the "pesos" theory.
* {{cite book |last=Cuhaj |first=George |title=Standard Catalog of United States Paper Money |publisher=Krause Publications, 28th Ed. |date=2009 |isbn=0-89689-939-X}}
* {{cite book |last=Ovason |first=David |title=The Secret Symbols of the Dollar Bill |publisher=Harper Paperbacks (reprint) |date=2004-11-30 |isbn=0-06-053045-6 | url= http://books.google.com/books?id=SGICN1DT1gsC&printsec=frontcover&dq=The+Secret+Symbols+of+the+Dollar+Bill}}
{{refend}}

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[[Category:Currency symbols]]
[[Category:Numismatics]]

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