At sign
From Wikipedia, the free encyclopedia
The typographic character @, called the at sign or at site or at symbol, is an abbreviation of the accounting and commercial invoice term, at the rate of (e.g. "7 widgets @ $2 = $14").
However in recent years its meaning has changed (or debatably it is increasingly used incorrectly) to also mean "at" in the sense of located at, especially in e-mail addresses.
Increasingly, @ is also used as a prefix to user names (e.g. "@username") on social websites such as Bebo and Twitter to denote a link, attribution or indirect reference.
The symbol was included on the keyboard of 1885 American Underwood, the first typewriter,[citation needed]. Raymond Tomlinson, an American programmer, used it in 1971 as the natural division within the first e-mail message sent.[1]
In English, it is usually pronounced at. Its official, typographic character name is commercial at in the ANSI, ITU-T, and Unicode character encoding standards. Some historical names are mentioned in the "History" section below.