Where did the @ symbol come from?

Computer programmer Ray Tomlinson died this week at the age of 74.  He definitely left his mark.

In 1971, Tomlinson invented email. As if that isn’t enough, he also first used @ – the at sign – to separate the username from the domain in the first electronic mail, now the standard symbol around the world.

The at sign, also known as the commercial at, has many other colorful names across the globe, including words for monkey, snail, and puppy in a number of languages.

Thanks to Tomlinson, @ now prevails in digital correspondence, but the symbol previously served commerce: accountants once used @ to abbreviate “at a rate of.” For instance, 10 pencils @ $1: 10 pencils at a rate of $1, or $10.

Tomlinson invented email as a way to send messages from one computer to another, a problem the US government recruited him to solve. To do so, the user and the host names needed some sort of punctuation mark to separate them. Tomlinson has since explained he chose @ because not only was it available, as it was not widely used, but also because it handily communicated a sense of location.

Hicks at Utah, or HICKS@UTAH, is an early example of @’s usage, as the Oxford English Dictionary (OED) records. The OED first dates the email @ to 1972, while the commercial @ is cited yet earlier in 1969.

But as a symbol, @ is much older.

The OED notes the “earliest evidence so far found for the symbol is in 16th-cent. European mercantile records.” The dictionary points to its usage as an Italian unit of measurement, called the anfora, as well as a Spanish and Portuguese one, the arroba.

Anfora, or amphora in English, measured about 9 gallons for the Greeks, apparently, and 6 gallons, 7 pints for the Romans, the OED explains. The two-handled vessel, the amphora, is the inspiration for the name and the unit of measurement. As used in this sense, amphora is attested in English by 1607. The Spanish arroba actually derives from Arabic – al-rub, a weight one “quarter” of a Spanish quintal – and thus typically measured about 25 Spanish pounds. Arroba, the OED tells us, is recored by 1598.

Several theories attempt to explain @’s distinctive spiral. Most converge on medieval manuscript shorthand for high-frequency words, like at, a significant efficiency when we consider the labor and expense required to produce and copy manuscripts. Some say @ wraps the e in each around the a in at; others, the curve abbreviates the t in at’s a. Yet others look to Latin’s ad (“to” or “at), with the symbol’s loop preserving an earlier way of writing lowercase d. In French, this at would be à, so @ saves writers from lifting their pens due to the accent mark, as it apparently can today.

If @ is first evidenced in medieval manuscripts, I, for one, would look to the Romance languages for the origin of this symbol and abbreviation.

Wherever @ comes from, one thing’s for sure: thanks to his technological (and typographical) genius, Tomlinson has made sure this once obscure and obsolescent symbol won’t be going anywhere anytime soon.

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