Ampersand
The ampersand is the logogram, representing the conjunction "and". It originated as a ligature of the letters et—Latin for "and".
Etymology
Traditionally, when reciting the alphabet in English-speaking schools, any letter that could also be used as a word in itself was repeated with the Latin expression :wikt:per se|per se, as in "A per se A". 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. 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 thorn, wynn, 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".
History
The ampersand can be traced back to the 1st century A.D. and the Old Roman cursive, in which the letters E and T occasionally were written together to form a ligature. 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 examples of how the et-ligature could look in this script. During the later development of the Latin script leading up to Carolingian minuscule the use of ligatures in general diminished. The et-ligature, however, continued to be used and gradually became more stylized and less revealing of its origin.The modern italic type ampersand is a kind of ":wikt:et|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 character at the end of the Latin alphabet, as for example in Byrhtferð's list of letters from 1011. Similarly, was regarded as the 27th letter of the English alphabet, as taught to children in the US and elsewhere. An example may be seen in M. B. Moore's 1863 book The Dixie Primer, for the Little Folks. In her 1859 novel Adam Bede, George Eliot refers to this when she makes Jacob Storey say: "He thought it
The ampersand should not be confused with the Tironian "et", which has the same meaning, but which in appearance resembles the numeral. Both symbols have their roots in the classical antiquity, and both signs were used throughout the Middle Ages as a representation for the Latin word et. However, while the ampersand was in origin a common ligature in everyday script, the Tironian et was part of a highly specialised stenographic shorthand. The Tironian et is found in Old Irish language script, a Latin-based script generally only used for decorative purposes today, where it signifies agus in Irish. This symbol may have entered the script language by way of monastic influence in the time of the early Christian church in Ireland.
Writing the ampersand
In everyday handwriting, the ampersand is sometimes simplified in design as a large lowercase epsilon or a reversed numeral, superimposed by a vertical line. The ampersand is also sometimes shown as an epsilon with a vertical line above and below it or a dot above and below it.The plus sign is often informally used in place of an ampersand, sometimes with an added loop and resembling.
Usage
Ampersands are commonly seen in business names formed from partnership of two or more people, such as Johnson & Johnson, Dolce & Gabbana, Marks & Spencer, A&P, and Tiffany & Co., as well as some abbreviations containing the word and, such as AT&T, R&D, D&B, R&B, B&B, and P&L.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. 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. In the list of references, an ampersand precedes the last author's name when there is more than one author.
The phrase et cetera, usually written as etc. can be abbreviated &c. representing the combination et + c.
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.
The ampersand may still be used as an abbreviation for "and" in informal writing regardless of how "and" is used.
Computing
Encoding and display
The character in Unicode is ; this is inherited from the same value in ASCII.Apart from this, Unicode also has the following variants:
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. It is almost always available on keyboard layouts, sometimes on or. On the AZERTY keyboard layout, is an unmodified keystroke, positioned above.
In URLs, the ampersand must be replaced by
%26 when representing a string character to avoid interpretation as a [|URL syntax character].Programming languages
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, and more differentiate between:
- for bitwise AND. is zero, is 4.
- for short-circuit logical AND. is true.
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 many implementations of ALGOL 60 the ampersand denotes the tens exponent of a real number.
In Common Lisp, the ampersand is the prefix for lambda list keywords.
Ampersand is the string concatenation operator in many BASIC dialects, AppleScript, Lingo, HyperTalk, 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.
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's ROM.
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 for decimal 255, for instance in BBC BASIC. Some other languages, such as the Monitor 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 VICE emulator.
In MySQL, has dual roles. As well as a logical AND, it additionally serves as the bitwise operator of an intersection between elements.
Dyalog APL uses ampersand similarly to [|Unix shells], spawning a separate green thread upon application of a function.
In more recent years, the ampersand has made its way into the Haskell standard library, representing flipped function application: means the same thing as.
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
- In Perl 5, it can still be used to modify the way user-defined subroutines are called
- In Perl 6, the ampersand sigil is only used when referring to a subroutine as an object, never when calling it
Ampersand is the name of a reactive programming language, which uses relation algebra to specify information systems.
Text markup
In SGML, XML, and HTML, the ampersand is used to introduce an SGML entity, such as or . The HTML and XML encoding for the ampersand character is the entity. 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 fonts, so it can be entered as in running text when using the default fonts.
In Microsoft Windows menus, labels, and other captions, the ampersand is used to denote the next letter as a keyboard shortcut. For instance setting a button label to makes it display as rint and for to be a shortcut equivalent to pressing that button. 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, and is also copied into many other toolkits on multiple operating systems. Sometimes this causes problems similar to other programs that fail to sanitize markup from user input, for instance Navision databases have trouble if this character in either "Text" or "Code" fields.
Unix shells
Some Unix shells use the ampersand as a metacharacter:Some Unix shells, like the POSIX standard
sh shell, use an 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.
Web standards