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Ampersand

From Wikipedia, the free encyclopedia
This article is about the symbol. For the magazine, see Ampersand (magazine). For the not-for-profit organisation, see Ampersand Network. For songs and albums called &, see & (disambiguation).
"&" redirects here. For other uses, see And.
&
Ampersand
Punctuation
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Word dividers
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General typography
ampersand&
asterisk*
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Intellectual property
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 ​ ฿ ​  ​¢ ​ ​ ​ $ ​ ​ ​  ​ ​ ƒ ​ ​  ​  ​ ​  ​  ​ ​  ​  ​ ​ ​£ ​  ​ ​  ​  ​  ​ ​  ​ ¥
Uncommon typography
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hedera
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Related
In other scripts
The ampersand is the logogram "&", representing the conjunction word "and". It originated as a ligature of the letters etLatin for "and".[1]

Etymology[edit]

The word ampersand is a corruption of the phrase "and per se & (and)", meaning "and intrinsically the word and (represented by the symbol &)".[2]
Traditionally, when reciting the alphabet in English-speaking schools, any letter that could also be used as a word in itself ("A", "I", and, at one point, "O") was repeated with the Latin expression per se ("by itself").[3][4][5] This habit was useful in spelling where a word or syllable was repeated after spelling; e.g. "d, o, g—dog" would be clear but simply saying "a—a" would be confusing without the clarifying "per se" added. It was also common practice to add the "&" sign at the end of the alphabet as if it were the 27th letter, pronounced as the Latin et or later in English as and. As a result, the recitation of the alphabet would end in "X, Y, Z, and per se and". This last phrase was routinely slurred to "ampersand" and the term had entered common English usage by 1837.[4][6][7] However, in contrast to the 26 letters, the ampersand does not represent a speech sound—although other characters that were dropped from the English alphabet did, such as the Old English thornwynn, and eth.
Through popular etymology, it has been falsely claimed that André-Marie Ampère used the symbol in his widely read publications and that people began calling the new shape "Ampère's and".[8]

History[edit]


Evolution of the ampersand

The modern ampersand is virtually identical to that of the Carolingian minuscule. The italic ampersand, to the right, is originally a later et-ligature.

Et ligature in Insular script

Example of ampersand based on a crossed epsilon, as might be handwritten.

Some modern fonts, likeTrebuchet MS, employ ampersand characters that reveal its origin
The ampersand can be traced back to the 1st century A.D. and the OldRoman cursive, in which the letters E and T occasionally were written together to form a ligature (figure 1). In the later and more flowing New Roman Cursive, ligatures of all kinds were extremely common; figures 2 and 3 from the middle of 4th century are both examples of how the et-ligature could look in this script. However, during the following development of the Latin script that led up to the Carolingian minuscule(9th century), while the use of ligatures in general diminished, the et-ligature continued to be used and gradually became more stylized and less revealing of its origin (figures 4–6).[9]
The modern italic type ampersand is a kind of "et" ligature that goes back to the cursive scripts developed during the Renaissance. After the advent of printing in Europe in 1455, printers made extensive use of both the italic and Roman ampersands. Since the ampersand's roots go back to Roman times, many languages that use a variation of the Latin alphabet make use of it.
The ampersand often appeared as a letter at the end of the Latin alphabet, as for example inByrhtferð's list of letters from 1011.[10] Similarly, & was regarded as the 27th letter of the English alphabet, as used by children (in the US). An example may be seen in M. B. Moore's 1863 book The Dixie Primer, for the Little Folks.[11] In her 1859 novel Adam BedeGeorge Eliot refers to this when she makes Jacob Storey say: "He thought it [Z] had only been put to finish off th' alphabet like; though ampusand would ha' done as well, for what he could see."[12] The popular Apple Pie ABC finishes with the lines "X, Y, Z, and ampersand, All wished for a piece in hand".
The ampersand should not be confused with the Tironian "et" ("⁊"), which is a symbol similar to the numeral 7. Both symbols have their roots in the classical antiquity, and both signs were used up through the Middle Ages as a representation for the Latin word "et" ("and"). However, while the ampersand was in origin a common ligature in the everyday script, the Tironian "et" was part of a highly specialised stenographic shorthand.[13]

Writing the ampersand[edit]

In everyday handwriting, the ampersand is sometimes simplified in design as a large lowercase epsilon (Ɛ) or a backwards numeral 3 superimposed by a vertical line. The ampersand is also often shown as a backwards 3 with a vertical line above and below it or a dot above and below it.
The + sign is often informally used in place of an ampersand, sometimes with an added loop and resembling ɬ.

Usage[edit]

Ampersands are commonly seen in business names formed from partnership of two or more people, such as Johnson & JohnsonDolce & GabbanaMarks & SpencerA&P (supermarkets), and Tiffany & Co., as well as some abbreviations containing the word and, such as AT&T(American Telephone and Telegraph), R&D (research and development), R&B (rhythm and blues), B&B (bed and breakfast), and P&L (profit and loss).[15][16]
In film credits for stories, screenplays, etc., & indicates a closer collaboration than and. The ampersand is used by the Writers Guild of America to denote two writers collaborating on a specific script, rather than one writer rewriting another's work. In screenplays, two authors joined with &collaborated on the script, while two authors joined with and worked on the script at different times and may not have consulted each other at all.[17][18] In the latter case, they both contributed enough significant material to the screenplay to receive credit but did not work together.
In APA style, the ampersand is used when citing sources in text such as (Jones & Jones, 2005). In the list of references, an ampersand precedes the last author's name when there is more than one author.[19] (This does not apply to MLA style, which calls for the "and" to be spelled.[20])
The phrase et cetera ("and so forth"), usually written as etc. can be abbreviated &c. representing the combination et + c(etera).
The ampersand can be used to indicate that the "and" in a listed item is a part of the item's name and not a separator (e.g. "Rock, pop, rhythm & blues, and hip hop").
The ampersand may still be used as an abbreviation for "and" in informal writing regardless of how "and" is used.

Computing[edit]

Encoding and display[edit]

The character in Unicode is U+0026 & ampersand (HTML & · &); this is inherited from the same value in ASCII.
Apart from this, Unicode also has the following variants:
  • U+FE60  small ampersand (HTML )
  • U+FF06  fullwidth ampersand (HTML  · in block Halfwidth and Fullwidth Forms)
  • U+214B  turned ampersand (HTML )
  • U+1F670 🙰 script ligature et ornament (HTML )
  • U+1F671 🙱 heavy script ligature et ornament (HTML )
  • U+1F672 🙲 ligature open et ornament (HTML )
  • U+1F673 🙳 heavy ligature open et ornament (HTML )
  • U+1F674 🙴 heavy ampersand ornament (HTML )
  • U+1F675 🙵 swash ampersand ornament (HTML )
The last six of these are carryovers from the Wingdings fonts, and are meant only for backward compatibility with those fonts.
On the QWERTY keyboard layout, the ampersand is  Shift+7. It is almost always available on keyboard layouts, sometimes on  Shift+6 or  Shift+8. On the AZERTYkeyboard layout, & is an unmodified keystroke, positioned above A.
In URLs, the ampersand must be replaced by %26 when representing a string character to avoid interpretation as a URL syntax character.

Programming languages[edit]

In the 20th century, following the development of formal logic, the ampersand became a commonly used logical notation for the binary operator or sentential connective AND. This usage was adopted in computing.
Many languages with syntax derived from C, including C++Perl,[21] and more differentiate between:
In CC++, and Go, a prefix "&" is a unary operator denoting the address in memory of the argument, e.g. &x, &func, &a[3].
In C++ and PHP, unary prefix & before a formal parameter of a function denotes pass-by-reference.
In Fortran, the ampersand forces the compiler to treat two lines as one. This is accomplished by placing an ampersand at the end of the first line and at the beginning of the second line.
In Common Lisp, the ampersand is the prefix for lambda list keywords.[22]
Ampersand is the string concatenation operator in many BASIC dialectsAppleScriptLingoHyperTalk, and FileMaker. In Ada it applies to all one-dimensional arrays, not just strings.
BASIC-PLUS on the DEC PDP-11 uses the ampersand as a short form of the verb PRINT.
Applesoft BASIC used the ampersand as an internal command, not intended to be used for general programming, that invoked a machine language program in the computer'sROM.
In some versions of BASIC, unary suffix & denotes a variable is of type long, or 32 bits in length.
The ampersand is occasionally used as a prefix to denote a hexadecimal number, such as &FF for decimal 255, for instance in BBC BASIC. Some other languages, such as theMonitor built into ROM on the Commodore 128, used it to indicate octal instead, a convention that spread throughout the Commodore community and is now used in the VICEemulator.
In MySQL the '&' has dual roles. As well as a logical AND, it additionally serves as the bitwise operator of an intersection between elements.
In more recent years, the ampersand has made its way into the Haskell standard library, representing flipped function applicationx & f means the same thing as f x.
The ampersand character is used as a special character in at least some versions of the database software originally created in Denmark under the name Navision (the software has since been acquired by Microsoft). Using this character in either "Text" or "Code" fields could create difficulties for performing certain tasks in Navision, such as filtering records (either by the user or by programming). It is also used as described below to indicate shortcuts in menu items and labels.
Perl uses the ampersand as a sigil to refer to subroutines:
  • In Perl 4 and earlier, it was effectively required to call user-defined subroutines[23]
  • In Perl 5, it can still be used to modify the way user-defined subroutines are called[24]
  • In Perl 6, the ampersand sigil is only used when referring to a subroutine as an object, never when calling it[25]
Ampersand is the name of a programming language, which uses relation algebra to specify information systems.[26]

Text markup[edit]

In SGMLXML, and HTML, the ampersand is used to introduce an SGML entity. The HTML and XML encoding for the ampersand character is the entity "&".[27] This can create a problem known as delimiter collision when converting text into one of these markup languages. For instance, when putting URLs or other material containing ampersands into XML format files such as RSS files the & must be replaced with & or they are considered not well formed, and computers will be unable to read the files correctly. SGML derived the use from IBM Generalized Markup Language, which was one of many IBM-mainframe languages to use the ampersand to signal a text substitution, eventually going back to System/360 macro assembly language.
In the plain TeX markup language, the ampersand is used to mark tabstops. The ampersand itself can be applied in TeX with \&. The Computer Modern fonts replace it with an "E.T." symbol in the cmti#(text italic) fonts, so it can be entered as {\it\&} in running text when using the default (Computer Modern) fonts.[28]
In Microsoft Windows menus, labels, and other captions, the ampersand is used to denote the keyboard shortcut for that option (Alt + that letter, which appears underlined). A double ampersand is needed in order to display a real ampersand. This convention originated in the first WIN32 api, and is used in Windows Forms,[29] and is also copied into many other tookits on multiple operating systems.

Unix shells[edit]

Some Unix shells use the ampersand as a metacharacter:
Some Unix shells, like the POSIX standard sh shell, use the ampersand to execute a process in the background and to duplicate file descriptors.
  • In Bash, the ampersand can separate words, control the command history, duplicate file descriptors, perform logical operations, control jobs, and participate in regular expressions.[30]

Web standards[edit]

The generic URL (Uniform Resource Locator) syntax allows for a query string to be appended to a file name in a web address so that additional information can be passed to a script; the question mark, or query mark, ?, is used to indicate the start of a query string. A query string is usually made up of a number of different name–value pairs, each separated by the ampersand symbol, &. For example, www.example.com/login.php?username=test&password=blank. But see also "Ampersands in URI attribute values".