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

@ symbol used as the initial "a" for the "amin" (amen) formula in the Bulgarian translation of the Manasses Chronicle, Template:C..<ref name="Vat slav">Template:Cite web</ref>
The Aragonese @ symbol used in the 1448 Template:Lang registry to denote a wheat shipment from Castile to the Kingdom of Aragon.<ref name="JoRom">Template:Cite web</ref><ref name="MoMA" />
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@ used to signify French "Template:Lang" ("at") from a 1674 protocol from a Swedish court (Template:Lang)

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 Template: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" (Template:Lang pronounced ar-rubʿ).<ref>Template:Cite web</ref> A symbol resembling an @ is found in the Spanish Template: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 (Template: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 Template: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">Template:Cite web</ref><ref name="Germain-2025">Template:Cite 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">Template:Cite web</ref><ref name="View-550712">Template:Cite web</ref><ref>Template:Cite 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>Template:Cite 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>Template:Cite 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 Template:Code 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>Template:Cite 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>Template:Cite web</ref>
  • 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>Template:Cite 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: Template:Code 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>Template:Cite web</ref><ref>Template:Cite web</ref>
  • In Assembly language, @ is sometimes used as a dereference operator.<ref>Template:Cite web</ref>
  • In CSS, @ is used in special statements outside of a CSS block.<ref>Template:Cite web</ref>
  • 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>Template:Cite 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>Template:Cite web</ref>
  • 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 Template:Code, 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>Template:Cite web</ref>
  • In J, denotes function composition.
  • In Java, it has been used to denote annotations, a kind of metadata, since version 5.0.<ref>Template:Cite web</ref>
  • In Julia, it denotes the invocation of a macro.<ref>Template:Cite web</ref>
  • 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>Template:Cite web</ref>
  • 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>Template:Cite web</ref>
  • In Pascal, @ is the "address of" operator (it tells the location at which a variable is found).
  • In Perl, @ prefixes variables which contain arrays Template:Code, including array slices Template:Code and hash slices Template:Code or Template:Code. 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>Template:Cite web</ref>
  • 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.<ref>Template:Cite web</ref>
  • In R and S-PLUS, it is used to extract slots from S4 objects.<ref>Template:Cite web</ref>
  • In Razor, it is used for C# code blocks.<ref>Template:Cite web</ref>
  • In Ruby, it functions as a sigil: @ prefixes instance variables, and @@ prefixes class variables.<ref>Template:Cite web</ref>
  • In Rust, it is used to bind values matched by a pattern to a variable.<ref>Template:Cite web</ref>
  • In Scala, it is used to denote annotations (as in Java), and also to bind names to subpatterns in pattern-matching expressions.<ref>Template:Cite 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: Template:Code to show the word "HELLO" in line 1, column 1.
  • 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 Template:Code which not only switches off echoing but prevents the command line itself from being echoed.<ref>Template:Cite web</ref><ref>Template:Cite web</ref>
  • In Windows PowerShell, @ is used as array operator for array and hash table literals and for enclosing here-string literals.<ref>Template:Cite web</ref>

Gender neutrality in Spanish

File:Madrid - Acampada Sol - 110521 192211.jpg
Protester with banner showing "La revolución está en nosotr@s"

Template:Main 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>Template:Cite web</ref>

Other uses and meanings

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File:Atletter.svg
Bicameral @ letter as used in the Koalib language.
File:OCR-A char Commercial At.svg
X-SAMPA uses an @ as a substitute for ə, which it resembles in some fonts.

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.

File:Basic interpreter on the DVK computer.JPG
@ on a DVK Soviet computer (Template:Circa)

Unicode

See also

References

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