At sign: Encyclopedia II - At sign - Modern uses

At sign - Modern uses

The symbol's most familiar modern use is in e-mail addresses (sent by SMTP), as in jdoe@example.com ("the user named ‘jdoe’ working at the computer named ‘example’ in the ‘com’ domain"). Ray Tomlinson is credited with the introduction of this use in 1972. This idea of user@host is seen in many other tools and protocols as well: for example, the command ssh jdoe@www.example.com would try to establish a ssh connection to the box 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 '$') 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 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.

In Pokémon communities, it is used as a symbol to denote Latios or 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 in some cases (obituaries, 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 may be difficult to produce in many computers.

In online discourse, the "@" sign is used by some anarchists as a substitute for the traditional circle-A.

Adapted from the Wikipedia article "Modern uses", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki