Software

Geek Trivia: Where the action is @

Who was the first software developer to use the @ symbol as an operator for routing e-mail, a fateful combination that has made both the symbol and the technology famous?

In Germany, they call it Klammeraffe, the spider monkey. In Hebrew, it's called strudel, as in the rolled pastry. Its Italian nickname is chiocciola, for snail; in Russian, it's called sobaka, for little dog; and in Greece, they call it the papaki, which means duckling. In the English-speaking world, however, we know this symbol, @, as the at sign.

Strictly speaking, by current Unicode standards, the official name for the @ symbol is the commercial at. Most folks didn't encounter the @ until they became regular e-mail users, which has led to a common misconception that the @ symbol was created for, if not e-mail, then at least computer software in general. Not so.

The @ symbol was included in the original ASCII character set in 1963, and ASCII was created largely for the benefit of teletype, not computer systems. (Although early computer developers found ASCII very handy.) Moreover, the original ASCII codifiers didn't generate the @ symbol from whole cloth, as this odd little be-swirled letter has appeared on typewriter keyboards since at least 1902. So where, exactly, did the @ symbol come from, and what did it mean before it found a use in e-mail addresses?

Back to the multilingual nicknames for @, let's take a look at the Spanish version of the term, arroba. The etymology of this term comes from the Roman (which is to say Latin) word, amphora, which was a clay urn of roughly standard size used for overseas shipping. Thus, the @ symbol's origin comes from shipping and trade.

Those of you with an actuarial background may have seen a phrase similar to this: 10 units @ $1. This refers to 10 units priced at one dollar each, for a total cost of 10 dollars. This is distinct from 10 units at $1, which means 10 units bought at a total cost of one dollar. In such cases, the @ was pronounced as at when ledgers were read aloud. This usage dates back to at least the 19th century, if not earlier.

That explains where the @ symbol came from before e-mail, but surely both @ and e-mail have been synonymous since the latter was created. Again, not so. E-mail existed in various forms before it was ever associated with @ sign, and it took one particular techie to decide that the @ operator would be perfect for this then-new communications medium.

WHO WAS THE FIRST SOFTWARE DEVELOPER TO USE THE @ SIGN TO ROUTE E-MAIL COMMUNICATIONS?

The developer in question is Ray Tomlinson, who worked on both ARPAnet, the precursor to the modern Internet, and TENEX, an early mainframe operating system. Tomlinson is often cited as the outright inventor of e-mail, a claim that is inaccurate and one that Tomlinson himself denies. The accolade which is due Tomlinson is that he sent the first Internet e-mail, and he was the first to use the @ sign as an address operator.

The first e-mail, by most accounts, was sent in 1965 at the Massachusetts Institute of Technology between users of the Compatible Timesharing System (CTSS) mainframe. CTSS users could post messages to each other, so that whenever the receiving user logged onto the mainframe, the message was waiting. (Actually, the new message was simply appended to a running message file, and each user got one, long, constantly updated message logfile.)

In 1971, Tomlinson was working on a similar message system for the TENEX operating system, called SNDMSG, as part of the ARPAnet team. He hit upon the idea of extending the functionality of SNDMSG to e-mail messages not to just users of the same mainframe, but to users of any mainframe connected to ARPAnet. In this case, he'd need an addressing system that indicated both the username and the host computer name. To combine these two data spaces, he chose the @ symbol because, in his words, "It made sense. At signs didn't appear in names so there would be no ambiguity about where the separation between login name and host name occurred."

Tomlinson sent the first Internet e-mail message in 1971 — he doesn't recall exactly when, though it was most likely late summer or early fall. The e-mail traveled between two DEC mainframes sitting side by side, but which were connected exclusively through ARPAnet. Tomlinson tested the technology with a standard qwertyuiop-style nonsense message, but what Tomlinson describes as the first substantive message simply alerted all the local users to the availability of the new @ operator-enhanced ARPAnet e-mail — which is to say, it was a message from IT that e-mail was working. My, how little has changed in 37 years.

That's not just some symbolically circuitous symmetry, but an ASCII fantastic example of highly communicative Geek Trivia.

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About Jay Garmon

Jay Garmon has a vast and terrifying knowledge of all things obscure, obtuse, and irrelevant. One day, he hopes to write science fiction, but for now he'll settle for something stranger — amusing and abusing IT pros. Read his full profile. You can a...

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