The @ symbol (pronounced in English as the word "at"), has the official name "commercial at" under the ANSI/CCITT/Unicode character systems. It is often referred to informally as the "at symbol", the "at sign", or just "at".
The origin of the symbol is debated, but is most likely a cursive form of ā, or possibly à (the French word for "at"). It was most commonly used as an abbreviation in accounting and commercial invoices, in statements such as "7 widgets @ £2 ea. = £14". More recently, the @ symbol has become ubiquitous due to its use in email addresses.
Other names for the symbol include: about; acosta; ampersat or asperand (not to be confused with ampersand); amphora; ape; apothrope; aroba; arobase; atgry; atmark; cabbage; cat; cinnabun or cinnamon bun; commercial symbol; cyclone; each; masterspace; mercantile symbol; rose; schnable; scroll or scroll-a; snail; strudel; these; vortex; whirlpool; chisignuh; whishi-whishi; yurming; or whorl. Some of these are based on specialized usage, others are visual descriptions, and atgry (plural atgrynge) is a recurring joke proposed on Usenet as the answer to a pair of longstanding linguistic riddles — the singular atgry is a fourth word that ends in gry, along with angry, hungry, and gry; and the plural atgrynge provides a word that rhymes with orange.The alternative FAQ for alt.usage.english
@ appears to be the cursive form of ā, an abbreviation of an unknown word beginning with a. In medieval European manuscripts, abbreviations were generally indicated by drawing a line over or through the letters, as in the common for Jesus Christ (see Christogram), or # from lb for libra 'pound'. In the typeface of the Gutenberg Bible, ā stands for either an or am within words. However, it is not known which particular word gave rise to modern @.
Some linguists say @ first appeared in the Middle Ages, when monks used it to shorten the Latin word ad which means "at, toward, or by." Others claim that @ stood for the measurement of weight in Spain in the 1400s. The measurement was "a jar" or an arroba, of something. Yet another contingent says @ was used by market sellers in the 1700s to show how much something might cost. They put signs like "5 potatoes @ 10 pence" in front of their stands.
A commonly accepted theory is that the symbol is derived from the Latin preposition ad, which means about with numerals. However, no document showing this usage has been presented.
A similar idea is that @ is the abbreviation of the Greek preposition ana (ανά), which means 'at the rate of' when used with numerals, exactly its modern commercial usage.
A more recent idea has been proposed by Giorgio Stabile, a professor of history in Rome. He claims to have traced the symbol back to the Italian Renaissance in a Venetian mercantile document signed by Francesco Lapi on May 4, 1536. The document talks about commerces with Pizarro and in particular the price of an @ of wine in Peru, where <@> stood for amphora (Italian anfora; Spanish and Portuguese arroba). The word arroba still means both the @ symbol and a unit of weight (see below). Under this view, the symbol was used to represent one amphora, which was a unit of weight or volume based upon the capacity of the standard terra cotta jar, and came into use with the modern meaning "at the rate of" in northern Europe.
However, @ could be the abbreviation of any word beginning in a, and more than one such symbol was likely in use, but there is no continuous record between any of the possibilities and the modern symbol.
An alternative view is that it derives from Norman French "à" meaning "at" in the sense of "each". "2 widgets à £5.50 = £11.00" is the sort of accountancy shorthand notation you will see on English commercial vouchers and ledgers all the way into the 1990s, where the usage was superseded for accountants with its e-mail usage. It is used in this way in Modern French also.
According to this view, the @ symbol is simply a stylish way of writing the à, so as not to remove the hand from the page in making the symbol. You can see hybrids between @ and à in French handwriting in street markets to this day.
The French call the symbol, among other things, "at" bâclé (using its English form). It may be that this is a deliberate pun on "atbash clé" - i.e. the ancient Hebrew key or cypher atbash - using a reversed alphabet - is to be used to decipher a hidden item of the text. There may even be a similar code indication of the ampersand - reading in German and French "am persan*" - i.e. "to Persian" - suggesting a language translation or perhaps reading R to L.
The @ symbol was present on the Lambert, a single element typewriter manufactured in 1902 by Lambert Typewriter Company of New York. It's inclusion in the original 1963 ASCII character set seems to have been unremarkable, so it was probably a standard character on commercial typewriters by that time.
ssh jdoe@www.example.com would try to establish a ssh connection to the computer with the hostname www.example.com using the username jdoe.
In the programming language Perl, the symbol prefixes variables which contain arrays, as opposed to scalar values (indicated with 'sign|$" target="_blank" >*') and hash tables / associative arrays ('%'). If the code were to be treated as a sentence, this prefix would be the equivalent of a determiner, so "@animals" might be read as "these animals".
In the IRC protocol, @ is the symbol for a channel operator. IRC also uses the user@host form (often preceded by nick!) for identifying and banning users. In this case the user@ part was originally an ident response and the host part was a reverse dns name from the user's IP. However, most modern IRC networks provide some mechanism for users to hide their real reverse dns hostname and/or for admins/privileged users to pick one arbitrarily.
The @ character is also used as an alternative political spelling for typing in some Romance languages as a gender-neutral substitute for the masculine "o" in mixed gender groups and in cases where the gender is unknown. For example, the Spanish word "amigos," which could either mean male and female "friends" or all male "friends" would be replaced with "amig@s." The character is intended to resemble a mix of the masculine letter "o" and the feminine "a". The usefulness of this is debated; in Spanish the masculine grammatical gender may include both males and females, while the feminine gender is exclusive to females, and there is no neutral gender. Some advocates of gender-neutral language-modification feel that using the male grammatical gender as a generic gender indicates an implicit linguistic disregard for women. Many Spanish speakers feel that this use of the "@" degrades their language, and some allege that it is an example of cultural imperialism. This construction is generally only used in informal writing. There is no established pronunciation of this writing. Alternative forms would be amigos/as and amigⒶs using the circle-A of anarchism.
In a similar fashion, Pokémon fans often write "Lati@s" to denote Latios and Latias.
In most roguelike games (such as NetHack), the "@" sign is used to denote the player character (or more generally, any human).
The "@" sign is also used sometimes (for example in articles relating to missing persons, obituaries, or brief reports) to denote an alias after a person's proper name, for instance: "John Smith @ Jean Smyth".
@ may sometimes be used to represent a schwa, as the actual schwa character "ə" may be difficult to produce in many computers. It is used in this capacity in the ASCII IPA or Kirshenbaum IPA scheme.
In online discourse, the "@" sign is used by some anarchists as a substitute for the traditional circle-A.
It is frequently used in Leet as a substitute for the letter A.
In the MMORPG game MapleStory, players who buy and sell items use long strings of "@" signs to heighten their chat bubbles and make their messages easier to see. The "@" sign is very wide compared to other ASCII characters, making it practical for this purpose.
In Malagasy, @ is an informal abbreviation for amin'ny.
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