At sign

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The at sign (Template:Char) is a typographical symbol used as an accounting and invoice abbreviation meaning "at a rate of" (e.g. 7 widgets @ £2 per widget = £14),<ref>See, for example, Browns Index to Photocomposition Typography (p. 37), Greenwood Publishing, 1983, Template:ISBN</ref> and now seen more widely in email addresses and social media platform handles. In English, it is normally read aloud as "at", and is also commonly called the at symbol, commercial at, or address sign. Most languages have their own name for the symbol.

Although not included on the keyboard layout of the earliest commercially successful typewriters, it was on at least one 1889 model<ref>"The @-symbol, part 2 of 2" Template:Webarchive, Shady Characters ⌂ The secret life of punctuation Template:Webarchive</ref> and the very successful Underwood models from the "Underwood No. 5" in 1900 onward. It started to be used in email addresses in the 1970s, and is now routinely included on most types of computer keyboards.

History

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The earliest yet discovered symbol in this shape is found in a 1345 Bulgarian translation of a Greek chronicle written by Constantinos Manasses. Held today in the Vatican Apostolic Library, the initial letter of the word {{#invoke:Lang|lang}} [amen] looks like an at sign.<ref name="Vat slav" />

The symbol 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" ({{#invoke:Lang|lang}} pronounced ar-rubʿ).<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> A symbol resembling an @ is found in the Spanish {{#invoke:Lang|lang}}, a registry to denote a wheat shipment from Castile to Aragon, in 1448.<ref name="JoRom" /> The historian Giorgio Stabile reports having traced the @ symbol to the 16th century, in a mercantile document sent by Florentine Francesco Lapi from Seville to Rome on May 4, 1536, stating that the symbol was interpreted to mean amphora ({{#invoke:Lang|lang}}), a unit of weight and volume based upon the capacity of the standard amphora jar since the 6th century. The document is about commerce with Pizarro, in particular the price of an @ of wine in Peru.<ref name="Willan-2000">Template:Cite news</ref>

The symbol could also mean adi (standard Italian {{#invoke:Lang|lang}}, i. e. ‘on the day of’) as used on a health pass in Northern Italy in 1667.<ref>Template:Cite journal</ref>

In 2010, the Museum of Modern Art (MoMA) added the @ symbol to its design collection.<ref name="MoMA">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="Germain-2025">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> In 2025, it was also included in MoMA's Pirouette: Turning Points in Design, an exhibition of "widely recognized design icons [...] highlighting pivotal moments in design history," alongside the I ♥ NY logo, Google map pins, and original 1980s Mac GUI icons, and the NASA Worm insignia.<ref name="Feeney-20252">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="View-550712">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="Germain-2025" />

Name

The name of the symbol arises from its original use in showing quantities and their price per unitTemplate:Snd for example, "10 widgets @ £1.50 each". The precise origin of the symbol is uncertain.<ref>Template:Cite encyclopedia</ref>

The absence of a single English word for the symbol has prompted some writers to use the French arobase,<ref>Template:Cite journal</ref> to coin new words such as ampersat<ref>Template:Cite news</ref> and asperand,<ref name="Kiss-2010">Template:Cite news</ref> or the (visual) onomatopoeia strudel,<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> but none of these have achieved wide use.

Modern use

Commercial usage

In contemporary English usage, @ is a commercial symbol, meaning at and at the rate of or at the price of. It has rarely been used in financial ledgers, and is not used in standard typography.<ref>Bringhurst, Robert (2002). The Elements of Typographic Style (version 2.5), p.272. Vancouver: Hartley & Marks. Template:ISBN.</ref>

Trademark

In 2012, "@" was registered as a trademark with the German Patent and Trade Mark Office.<ref>German Patent and Trademark Office, registration number 302012038338 Template:Webarchive.</ref> A cancellation request was filed in 2013, and the cancellation was ultimately confirmed by the German Federal Patent Court in 2017.<ref>Bundespatentgericht, decision of 22 February 2017, no. 26 W (pat) 44/14 (online Template:Webarchive).</ref>

Email addresses

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). Ray Tomlinson of BBN Technologies is credited for having introduced this usage in 1971.<ref name="Kiss-2010" /><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> This idea of the symbol representing located at in the form user@host is also seen in other tools and protocols; for example, it's used in some command-line utilities that connect to a remote host, such as Secure Shell (ssh jdoe@example.net tries to establish an ssh connection to the computer with the hostname example.net using the username jdoe).

On web pages, organizations often obscure the email addresses of their members or employees by omitting the @. This practice, known as address munging, attempts to make the email addresses less vulnerable to spam programs that scan the internet for them.

Social media

Template:Further On many social media platforms and forums, usernames or handles prefixed with an @ (in the form @johndoe) are interpreted as mentions of that user and may be treated specially.

On online forums without threaded discussions, @ is commonly used to denote a reply; for instance: @Jane to respond to a comment Jane made earlier. Similarly, in some cases, @ is used for "attention" in email messages originally sent to someone else. 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 <syntaxhighlight lang="text" class="" style="" inline="1">@Keirsten</syntaxhighlight> to signal to Keirsten that the following sentence concerns her.Template:Citation needed This also helps with mobile email users who might not see bold or color in email.

In microblogging (such as on Twitter, GNU social- and ActivityPub-based microblogs), an @ before the user name is used to send publicly readable replies (e.g. @otheruser: Message text here). The blog and client system interpret these as links to the user in question. 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 handle. A similar use of the @ symbol was added to Facebook on September 15, 2009.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> In Internet Relay Chat (IRC), it is shown before users' nicknames to denote they have operator status on a channel.

Computer languages

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

  • In ActionScript, @ is used in XML parsing and traversal as a string prefix to identify attributes in contrast to child elements.<ref>{{#invoke:citation/CS1|citation

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  • In Ada 2022, @ is the target name symbol, an abbreviation of the LHS of an assignment; it is used to avoid repetition of potentially long names in assignment statements.<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref> For example: A_Very_Long_Variable_Name := A_Very_Long_Variable_Name + 1; is shortened to A_Very_Long_Variable_Name := @ + 1;, increasing readability.

  • 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: <syntaxhighlight lang="text" class="" style="" inline="1">arrayx[@88]</syntaxhighlight> refers to an array starting at index 88.<ref>Template:Cite journal</ref>
  • In Dyalog APL, @ is used as a functional way to modify or replace data at specific locations in an array.
  • In the ASP.NET MVC Razor template markup syntax, the @ character denotes the start of code statement blocks or the start of text content.<ref>{{#invoke:citation/CS1|citation

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  • In CSS, @ is used in special statements outside of a CSS block.<ref>{{#invoke:citation/CS1|citation

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  • In C#, it denotes "verbatim strings", where no characters are escaped and two double-quote characters represent a single double-quote.<ref>2.4.4.5 String literals Template:Webarchive,</ref> As a prefix it also allows keywords to be used as identifiers,<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref> a form of stropping.

  • In D, it denotes function attributes: 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.<ref>{{#invoke:citation/CS1|citation

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  • 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.
  • In the Domain Name System (DNS), @ is used to represent the <syntaxhighlight lang="text" class="" style="" inline="1">$ORIGIN</syntaxhighlight>, typically the "root" of the domain without a prefixed sub-domain. (Ex: wikipedia.org vs. www.wikipedia.org)
  • In Forth, it is used to fetch values from the address on the top of the stack. The operator is pronounced as "fetch".
  • In Haskell, it is used in so-called as-patterns. This notation can be used to give aliases to patterns, making them more readable.
  • in HTML, it can be encoded as &commat;<ref>{{#invoke:citation/CS1|citation

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  • In Julia, it denotes the invocation of a macro.<ref>{{#invoke:citation/CS1|citation

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  • In LiveCode, it is prefixed to a parameter to indicate that the parameter is passed by reference.
  • 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.<ref>{{#invoke:citation/CS1|citation

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  • In a Makefile, @ specifies to not output the command before it is executed.
  • In ML, it denotes list concatenation.
  • 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").
  • In Objective-C, @ is prefixed to language-specific keywords such as @implementation and to form string literals.
  • In InterSystems ObjectScript, @ is the indirection operator, enabling dynamic runtime substitution of part or all of a command line, a command, or a command argument.<ref>{{#invoke:citation/CS1|citation

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  • In Pascal, @ is the "address of" operator (it tells the location at which a variable is found).
  • In Perl, @ prefixes variables which contain arrays <syntaxhighlight lang="text" class="" style="" inline="1">@array</syntaxhighlight>, including array slices <syntaxhighlight lang="text" class="" style="" inline="1">@array[2..5,7,9]</syntaxhighlight> and hash slices <syntaxhighlight lang="perl" class="" style="" inline="1">@hash{'foo', 'bar', 'baz'}</syntaxhighlight> or <syntaxhighlight lang="perl" class="" style="" inline="1">@hash{qw(foo bar baz)}</syntaxhighlight>. This use is known as a sigil.
  • In PHP, it is used just before an expression to make the interpreter suppress errors that would be generated from that expression.<ref>{{#invoke:citation/CS1|citation

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  • In R and S-PLUS, it is used to extract slots from S4 objects.<ref>{{#invoke:citation/CS1|citation

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  • In Razor, it is used for C# code blocks.<ref>{{#invoke:citation/CS1|citation

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  • In Rust, it is used to bind values matched by a pattern to a variable.<ref>{{#invoke:citation/CS1|citation

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  • In Scala, it is used to denote annotations (as in Java), and also to bind names to subpatterns in pattern-matching expressions.<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref>

  • 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.
  • In T-SQL, @ prefixes variables and @@ prefixes "niladic" system functions.
  • In several xBase-type programming languages, like DBASE, FoxPro/Visual FoxPro and Clipper, it is used to denote position on the screen. For example: <syntaxhighlight lang="xbase" class="" style="" inline="1">@1,1 SAY "HELLO"</syntaxhighlight> to show the word "HELLO" in line 1, column 1.

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  • In a Windows Batch file, an @ 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 <syntaxhighlight lang="text" class="" style="" inline="1">@echo off</syntaxhighlight> which not only switches off echoing but prevents the command line itself from being echoed.<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

  • In Windows PowerShell, @ is used as array operator for array and hash table literals and for enclosing here-string literals.<ref>{{#invoke:citation/CS1|citation

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Gender neutrality in Spanish

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Protester with banner showing "La revolución está en nosotr@s"

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} 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.<ref>Template:Cite journal</ref> For example, the word amigos traditionally represents not only male friends, but also a mixed group, or where the genders are not known. 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. The Real Academia Española disapproves of this usage.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Other uses and meanings

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Bicameral @ letter as used in the Koalib language.
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X-SAMPA uses an @ as a substitute for ə, which it resembles in some fonts.
  • In (especially English) scientific and technical literature, @ is used to describe the conditions under which data are valid or a measurement has been made. E.g. the density of saltwater may read d = 1.050 g/cm3 @ 15 °C (read "at" for @), density of a gas d = 0.150 g/L @ 20 °C, 1 bar, or noise of a car 81 dB @ 80 km/h (speed).<ref name="getproofed">{{#invoke:citation/CS1|citation

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  • In many roguelike games, @ is used to represent the player character.
  • In Spain and Portugal, the Arroba, abbreviated using the @ sign, is a customary unit of weight, mass or volume. The name arroba is used in both countries for the @ sign more generally.

Names in other languages

In many languages other than English, although most typewriters included the symbol, the use of @ was less common before email became widespread in the mid-1990s. Consequently, it is often perceived in those languages as denoting "the Internet", computerization, or modernization in general. Naming the symbol after animals is also common.

|CitationClass=web }}</ref> More recently,Template:When it is commonly referred to as {{#invoke:Lang|lang}}, as in English.

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  • In Norwegian, it is officially called {{#invoke:Lang|lang}} ('curly alpha' or 'alpha twirl'), and commonly as {{#invoke:Lang|lang}}. Sometimes {{#invoke:Lang|lang}}, the Swedish/Danish name (which means 'trunk A', as in 'elephant's trunk'), is used. Commonly, people will call the symbol {{#invoke:IPA|main}} (as in English), particularly when giving their email addresses. The computer manufacturer Norsk Data used it as the command prompt, and it was often called "grisehale" (pig's tail).
  • In Persian, it is {{#invoke:Lang|lang}}, {{#invoke:Lang|lang}}, from the English word.
  • In Polish, it is commonly called Template:Wikt-lang ('monkey'). Rarely, the English word at is used.
  • In Portuguese, it is called Template:Wikt-lang (from the Arabic {{#invoke:Lang|lang}}, Template:Wikt-lang). The word {{#invoke:Lang|lang}} is also used for a weight measure in Portuguese. One arroba is equivalent to 32 old Portuguese pounds, approximately Template:Convert, and both the weight and the symbol are called {{#invoke:Lang|lang}}. In Brazil, cattle are still priced by the {{#invoke:Lang|lang}} – now rounded to Template:Convert. This naming is because the at sign was used to represent this measure.
  • In Romanian, it is most commonly called {{#invoke:Lang|lang}}, but also colloquially called {{#invoke:Lang|lang}} ("monkey tail") or {{#invoke:Lang|lang}}. The latter is commonly used, and it comes from the word round (from its shape), but that is nothing like the mathematical symbol {{#invoke:Lang|lang}} (rounded A). Others call it {{#invoke:Lang|lang}}, or {{#invoke:Lang|lang}} (Romanian word for 'at').
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@ on a DVK Soviet computer (Template:Circa)
  • In Russian, it is commonly called {{#invoke:Lang|lang}} ({{#invoke:Lang|lang}} – '[little] dog').
  • In Serbian, it is called Template:Wikt-lang ({{#invoke:Lang|lang}} – 'crazy A'), Template:Wikt-lang ({{#invoke:Lang|lang}} – 'little monkey'), or Template:Wikt-lang ({{#invoke:Lang|lang}} – 'monkey').
  • In Slovak, it is called Template:Wikt-lang ('rollmop', a pickled fish roll, as in Czech).
  • In Slovenian, it is called {{#invoke:Lang|lang}} (an informal word for 'monkey').
  • In Spanish-speaking countries, it is called Template:Wikt-lang (from the Arabic {{#invoke:Lang|lang}}, which denotes a pre-metric unit of weight).
  • In Sámi (North Sámi), it is called {{#invoke:Lang|lang}} meaning 'cat's tail'.
  • In Swedish, it is called Template:Wikt-lang ('elephant's trunk A') or simply {{#invoke:Lang|lang}}, as in the English language. Less formally it is also known as Template:Wikt-lang ('cinnamon roll') or {{#invoke:Lang|lang}} ('alpha curl').
  • In Swiss German, it is commonly called {{#invoke:Lang|lang}} ('monkey-tail'). However, the use of the English word {{#invoke:Lang|lang}} has become increasingly popular in Swiss German, as with Standard German.Template:Citation needed
  • In Tagalog, the word Template:Wikt-lang means 'and', so the symbol is used like an ampersand in colloquial writing such as text messages (e.g. {{#invoke:Lang|lang}}, 'cook and eat').
  • In Thai, it is commonly called {{#invoke:Lang|lang}}, as in English.
  • In Turkish, it is commonly called {{#invoke:Lang|lang}}, a variant pronunciation of English at.Template:Citation needed
  • In Ukrainian, it is commonly called {{#invoke:Lang|lang}} ({{#invoke:Lang|lang}} – 'at') or Равлик (ravlyk), which means 'snail'.
  • In Urdu, it is {{#invoke:Lang|lang}} ({{#invoke:Lang|lang}}).
  • In Uzbek, it is commonly called {{#invoke:Lang|lang}} ('little dog').<ref>{{#invoke:citation/CS1|citation

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Unicode

See also

References

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