At sign

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"@" redirects here. At sign_sentence_0

For the letter A within a circle, see Enclosed A. At sign_sentence_1

For the album by John Zorn and Thurston Moore, see "@". At sign_sentence_2

For other uses, see Circled-a (disambiguation). At sign_sentence_3

At sign_table_infobox_0

@At sign_header_cell_0_0_0
At signAt sign_header_cell_0_1_0
In UnicodeAt sign_header_cell_0_2_0 U+0040 @ COMMERCIAL AT (HTML @ · @)At sign_cell_0_2_1
RelatedAt sign_header_cell_0_3_0
See alsoAt sign_header_cell_0_4_0 U+FF20 @ FULLWIDTH COMMERCIAL AT (HTML @)

U+FE6B ﹫ SMALL COMMERCIAL AT (HTML ﹫)At sign_cell_0_4_1

The at sign, @, is normally read aloud as "at"; it is also commonly called the at symbol or commercial at. At sign_sentence_4

It is used as an accounting and invoice abbreviation meaning "at a rate of" (e.g. 7 widgets @ £2 per widget = £14), but it is now seen more widely in email addresses and social media platform handles. At sign_sentence_5

The absence of a single English word for the symbol has prompted some writers to use the French arobase or Spanish and Portuguese arroba, or to coin new words such as ampersat, asperand, and strudel, but none of these has achieved wide use. At sign_sentence_6

The term alphasand is sometimes used, especially in East Asia. At sign_sentence_7

Although not included on the keyboard of the earliest commercially successful typewriters, it was on at least one 1889 model and the very successful Underwood models from the "Underwood No. At sign_sentence_8

5" in 1900 onward. At sign_sentence_9

It started to be used in email addresses in the 1970s, and is now universally included on computer keyboards. At sign_sentence_10

History At sign_section_0

The earliest yet discovered symbol in this shape is found in a Bulgarian translation of a Greek chronicle written by Constantinos Manasses in 1345. At sign_sentence_11

Held today in the Vatican Apostolic Library, it features the @ symbol in place of the capital letter alpha "Α" in the word Amen. At sign_sentence_12

Why it was used in this context is still a mystery. At sign_sentence_13

The evolution of the symbol as used today is not recorded. At sign_sentence_14

Whatever the origin of the @ symbol, the history of its usage is better known: it has long been used in Catalan, Spanish and Portuguese as an abbreviation of arroba, a unit of weight equivalent to 25 pounds, and derived from the Arabic expression of "the quarter" (الربع pronounced ar-rubʿ). At sign_sentence_15

An Italian academic, Giorgio Stabile, claims to have traced the @ symbol to the 16th century, in a mercantile document sent by Florentine Francesco Lapi from Seville to Rome on May 4, 1536. At sign_sentence_16

The document is about commerce with Pizarro, in particular the price of an @ of wine in Peru. At sign_sentence_17

Currently, the word arroba means both the at-symbol and a unit of weight. At sign_sentence_18

In Venetian, the symbol was interpreted to mean amphora (anfora), a unit of weight and volume based upon the capacity of the standard amphora jar since the 6th century. At sign_sentence_19

Until now the first historical document containing a symbol resembling a @ as a commercial one is the Spanish "Taula de Ariza", a registry to denote a wheat shipment from Castile to Aragon in 1448; even though the oldest fully developed modern @ sign is the one found on the above-mentioned Florentine letter. At sign_sentence_20

Modern use At sign_section_1

Commercial usage At sign_section_2

In contemporary English usage, @ is a commercial symbol, meaning at and at the rate of. At sign_sentence_21

It has rarely been used in financial ledgers, and is not used in standard typography. At sign_sentence_22

Trademark At sign_section_3

In 2012, "@" was registered as a trademark with the German Patent and Trade Mark Office. At sign_sentence_23

A cancellation request was filed in 2013, and the cancellation was ultimately confirmed by the German Federal Patent Court in 2017. At sign_sentence_24

Email addresses At sign_section_4

A common contemporary use of @ is in email addresses (using the SMTP system), as in jdoe@example.com (the user jdoe located at the domain example.com). At sign_sentence_25

BBN Technologies' Ray Tomlinson is credited with introducing this usage in 1971. At sign_sentence_26

This idea of the symbol representing located at in the form user@host is also seen in other tools and protocols; for example, the Unix shell command ssh jdoe@example.net tries to establish an ssh connection to the computer with the hostname example.net using the username jdoe. At sign_sentence_27

On web pages, organizations often obscure email addresses of their members or employees by omitting the @. At sign_sentence_28

This practice, known as address munging, makes the email addresses less vulnerable to spam programs that scan the internet for them. At sign_sentence_29

Social media At sign_section_5

Further information: Mention (blogging) At sign_sentence_30

On some social media platforms and forums, usernames are in the form @johndoe; this type of username is frequently referred to as a "handle". At sign_sentence_31

On online forums without threaded discussions, @ is commonly used to denote a reply; for instance: @Jane to respond to a comment Jane made earlier. At sign_sentence_32

Similarly, in some cases, @ is used for "attention" in email messages originally sent to someone else. At sign_sentence_33

For example, if an email was sent from Catherine to Steve, but in the body of the email, Catherine wants to make Keirsten aware of something, Catherine will start the line @Keirsten to indicate to Keirsten that the following sentence concerns her. At sign_sentence_34

This also helps with mobile email users who cannot see bold or color in email. At sign_sentence_35

In microblogging (such as Twitter and GNU social-based microblogs), @ before the user name is used to send publicly readable replies (e.g. @otheruser: Message text here). At sign_sentence_36

The blog and client software can automatically interpret these as links to the user in question. At sign_sentence_37

When included as part of a person's or company's contact details, an @ symbol followed by a name is normally understood to refer to a Twitter ID. At sign_sentence_38

A similar use of the @ symbol was also made available to Facebook users on September 15, 2009. At sign_sentence_39

In Internet Relay Chat (IRC), it is shown before users' nicks to denote they have operator status on a channel. At sign_sentence_40

Sports usage At sign_section_6

In American English the @ can be used to add information about a sporting event. At sign_sentence_41

Where opposing sports teams have their names separated by a "v" (for ), the away team can be written first - and the normal "v" replaced with @ to convey at which team's home field the game will be played. At sign_sentence_42

This usage is not followed in British English, since conventionally the home team is written first. At sign_sentence_43

Computer languages At sign_section_7

@ is used in various programming languages and other computer languages, although there is not a consistent theme to its usage. At sign_sentence_44

For example: At sign_sentence_45

At sign_unordered_list_0

  • In ALGOL 68, the @ symbol is brief form of the at keyword; it is used to change the lower bound of an array. For example: arrayx[@88] now refers to an array starting at index 88.At sign_item_0_0
  • In ActionScript, @ is used in XML parsing and traversal as a string prefix to identify attributes in contrast to child elements.At sign_item_0_1
  • In the ASP.NET MVC Razor template markup syntax, the @ character denotes the start of code statement blocks or the start of text content.At sign_item_0_2
  • In Dyalog APL, @ is used as a functional way to modify or replace data at specific locations in an array.At sign_item_0_3
  • In CSS, @ is used in special statements outside of a CSS block.At sign_item_0_4
  • In C#, it denotes "verbatim strings", where no characters are escaped and two double-quote characters represent a single double-quote. As a prefix it also allows keywords to be used as identifiers, a form of stropping.At sign_item_0_5
  • In D, it denotes function Atattributes: like: @safe, @nogc, user defined @('from_user') which can be evaluated at compile time (with __traits) or @property to declare properties, which are functions that can be syntactically treated as if they were fields or variables.At sign_item_0_6
  • In DIGITAL Command Language, the @ character was the command used to execute a command procedure. To run the command procedure VMSINSTAL.COM, one would type @VMSINSTAL at the command prompt.At sign_item_0_7
  • In Forth, it is used to fetch values from the address on the top of the stack. The operator is pronounced as "fetch".At sign_item_0_8
  • In Haskell, it is used in so-called as-patterns. This notation can be used to give aliases to patterns, making them more readable.At sign_item_0_9
  • In J, denotes function composition.At sign_item_0_10
  • In Java, it has been used to denote annotations, a kind of metadata, since version 5.0.At sign_item_0_11
  • In LiveCode, it is prefixed to a parameter to indicate that the parameter is passed by reference.At sign_item_0_12
  • In an LXDE autostart file (as used, for example, on the Raspberry Pi computer), @ is prefixed to a command to indicate that the command should be automatically re-executed if it crashes.At sign_item_0_13
  • In ML, it denotes list concatenation.At sign_item_0_14
  • In modal logic, specifically when representing possible worlds, @ is sometimes used as a logical symbol to denote the actual world (the world we are "at").At sign_item_0_15
  • In Objective-C, @ is prefixed to language-specific keywords such as @implementation and to form string literals.At sign_item_0_16
  • In Pascal, @ is the "address of" operator (it tells the location at which a variable is found).At sign_item_0_17
  • In Perl, @ prefixes variables which contain arrays @array, including array slices @array[2..5,7,9] and hash slices @hash{'foo', 'bar', 'baz'} or @hash{qw(foo bar baz)}. This use is known as a sigil.At sign_item_0_18
  • In PHP, it is used just before an expression to make the interpreter suppress errors that would be generated from that expression.At sign_item_0_19
  • In Python 2.4 and up, it is used to decorate a function (wrap the function in another one at creation time). In Python 3.5 and up, it is also used as an overloadable matrix multiplication operator.At sign_item_0_20
  • In Razor, it is used for C# code blocks.At sign_item_0_21
  • In Ruby, it functions as a sigil: @ prefixes instance variables, and @@ prefixes class variables.At sign_item_0_22
  • In Scala, it is used to denote annotations (as in Java), and also to bind names to subpatterns in pattern-matching expressions.At sign_item_0_23
  • In Swift, @ prefixes "annotations" that can be applied to classes or members. Annotations tell the compiler to apply special semantics to the declaration like keywords, without adding keywords to the language.At sign_item_0_24
  • In T-SQL, @ prefixes variables and @@ prefixes niladic system functions.At sign_item_0_25
  • In several xBase-type programming languages, like DBASE, FoxPro/Visual FoxPro and Clipper, it is used to denote position on the screen. For example: @1,1 SAY "HELLO" to show the word "HELLO" in line 1, column 1.At sign_item_0_26
  • In FoxPro/Visual FoxPro, it is also used to indicate explicit pass by reference of variables when calling procedures or functions (but it is not an address operator).At sign_item_0_27
  • In a Windows , the @ symbol at the start of a line suppresses the echoing of that command. In other words, is the same as ECHO OFF applied to the current line only. Normally a Windows command is executed and takes effect from the next line onward, but @ is a rare example of a command that takes effect immediately. It is most commonly used in the form @echo off which not only switches off echoing but prevents the command line itself from being echoed.At sign_item_0_28
  • In Windows PowerShell, @ is used as array operator for array and hash table literals and for enclosing here-string literals.At sign_item_0_29
  • In the Domain Name System, @ is used to represent the $ORIGIN, typically the "root" of the domain without a prefixed sub-domain. (Ex: wikipedia.org vs. www.wikipedia.org)At sign_item_0_30

Gender neutrality in Spanish At sign_section_8

Main article: Gender neutrality in Spanish At sign_sentence_46

In Spanish, where many words end in "-o" when in the masculine gender and end "-a" in the feminine, @ is sometimes used as a gender-neutral substitute for the default "o" ending. At sign_sentence_47

For example, the word amigos traditionally represents not only male friends, but also a mixed group, or where the genders are not known. At sign_sentence_48

The proponents of gender-inclusive language would replace it with amig@s in these latter two cases, and use amigos only when the group referred to is all-male and amigas only when the group is all female. At sign_sentence_49

The Real Academia Española disapproves of this usage. At sign_sentence_50

Other uses and meanings At sign_section_9

Variants At sign_section_10

At sign_table_general_1

Character informationAt sign_table_caption_1
PreviewAt sign_header_cell_1_0_0 @At sign_header_cell_1_0_1 At sign_header_cell_1_0_3 At sign_header_cell_1_0_5
Unicode nameAt sign_cell_1_1_0 COMMERCIAL ATAt sign_cell_1_1_1 FULLWIDTH COMMERCIAL ATAt sign_cell_1_1_3 SMALL COMMERCIAL ATAt sign_cell_1_1_5
EncodingsAt sign_header_cell_1_2_0 decimalAt sign_header_cell_1_2_1 hexAt sign_header_cell_1_2_2 decimalAt sign_header_cell_1_2_3 hexAt sign_header_cell_1_2_4 decimalAt sign_header_cell_1_2_5 hexAt sign_header_cell_1_2_6
UnicodeAt sign_cell_1_3_0 64At sign_cell_1_3_1 U+0040At sign_cell_1_3_2 65312At sign_cell_1_3_3 U+FF20At sign_cell_1_3_4 65131At sign_cell_1_3_5 U+FE6BAt sign_cell_1_3_6
UTF-8At sign_cell_1_4_0 64At sign_cell_1_4_1 40At sign_cell_1_4_2 239 188 160At sign_cell_1_4_3 EF BC A0At sign_cell_1_4_4 239 185 171At sign_cell_1_4_5 EF B9 ABAt sign_cell_1_4_6
Numeric character referenceAt sign_cell_1_5_0 @At sign_cell_1_5_1 @At sign_cell_1_5_2 At sign_cell_1_5_3 At sign_cell_1_5_4 At sign_cell_1_5_5 At sign_cell_1_5_6
Named character referenceAt sign_cell_1_6_0 @At sign_cell_1_6_1 At sign_cell_1_6_3 At sign_cell_1_6_5
ASCII and extensionsAt sign_cell_1_7_0 64At sign_cell_1_7_1 40At sign_cell_1_7_2 At sign_cell_1_7_3 At sign_cell_1_7_4 At sign_cell_1_7_5 At sign_cell_1_7_6
EBCDIC (037, 500, UTF)At sign_cell_1_8_0 124At sign_cell_1_8_1 7CAt sign_cell_1_8_2 At sign_cell_1_8_3 At sign_cell_1_8_4 At sign_cell_1_8_5 At sign_cell_1_8_6
EBCDIC (1026)At sign_cell_1_9_0 174At sign_cell_1_9_1 AEAt sign_cell_1_9_2 At sign_cell_1_9_3 At sign_cell_1_9_4 At sign_cell_1_9_5 At sign_cell_1_9_6
Shift JISAt sign_cell_1_10_0 64At sign_cell_1_10_1 40At sign_cell_1_10_2 129 151At sign_cell_1_10_3 81 97At sign_cell_1_10_4 At sign_cell_1_10_5 At sign_cell_1_10_6
EUC-JPAt sign_cell_1_11_0 64At sign_cell_1_11_1 40At sign_cell_1_11_2 161 247At sign_cell_1_11_3 A1 F7At sign_cell_1_11_4 At sign_cell_1_11_5 At sign_cell_1_11_6
EUC-KR / UHCAt sign_cell_1_12_0 64At sign_cell_1_12_1 40At sign_cell_1_12_2 163 192At sign_cell_1_12_3 A3 C0At sign_cell_1_12_4 At sign_cell_1_12_5 At sign_cell_1_12_6
GB 18030At sign_cell_1_13_0 64At sign_cell_1_13_1 40At sign_cell_1_13_2 163 192At sign_cell_1_13_3 A3 C0At sign_cell_1_13_4 169 136At sign_cell_1_13_5 A9 88At sign_cell_1_13_6
Big5At sign_cell_1_14_0 64At sign_cell_1_14_1 40At sign_cell_1_14_2 162 73At sign_cell_1_14_3 A2 49At sign_cell_1_14_4 162 78At sign_cell_1_14_5 A2 4EAt sign_cell_1_14_6
EUC-TWAt sign_cell_1_15_0 64At sign_cell_1_15_1 40At sign_cell_1_15_2 162 233At sign_cell_1_15_3 A2 E9At sign_cell_1_15_4 162 238At sign_cell_1_15_5 A2 EEAt sign_cell_1_15_6
LaTeXAt sign_cell_1_16_0 \MVAtAt sign_cell_1_16_1 At sign_cell_1_16_3 At sign_cell_1_16_5

See also At sign_section_11

At sign_unordered_list_1


Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/At sign.