The @ Sign: The Little Horned Beast That Conquered the World

Look at it for a second, that little whirl sitting in the middle of your email address. The @. You type it a hundred times a week without a thought, the way you slide a key into a lock. Yet this sign has crossed five centuries, changed jobs several times, and picked up a whole menagerie of funny nicknames along the way. Not bad for a character plenty of people assumed was invented alongside the internet.

A tale of merchants and market stalls

Before it went digital, the @ was commercial to the tips of its horns. In Anglo-Saxon account books it meant "at" in the sense of "at the unit price of". Three apples @ 2 francs, and the deal was done. That usage is what earned it a quiet but stubborn place on invoices and shopkeepers' slates.

Go back further and you stumble onto an older trail. The Italian historian Giorgio Stabile spotted the symbol in a letter from a Florentine merchant, Francesco Lapi, dated 1536. There the @ stood for an amphora, a unit of measure for wine and grain. That is probably where the French word arobase comes from, cousin to the Spanish arroba, an old unit of weight worth roughly eleven and a half kilos. And arroba itself is thought to descend from the Arabic ar-rub, "the quarter". In other words, your favourite symbol has one foot in Renaissance bookkeeping and the other in a merchant caravan. For a sign we file under "geek", the family tree cuts quite a figure.

Nearly dead on the keyboard

The @ could have ended up in a museum. In the early twentieth century it was already squatting on typewriters, reserved for accountants and bookkeepers. A key for insiders, really, wedged in a corner of the keyboard most people never grazed. When the first computers inherited those key layouts, the @ came along for the ride, partly out of habit, partly out of luck. It was there, available, and nobody was really using it. An orphan character waiting for its big break without knowing it.

1971: Ray Tomlinson's stroke of genius

Its big break came courtesy of an American engineer named Ray Tomlinson. In 1971 he was working at BBN, the company tinkering with the ancestor of the internet, ARPANET. Tomlinson wanted to send a message from one computer to another, across the network. The snag: he needed a clean way to say "this user, on that machine". He scanned his keyboard for a symbol that would never turn up inside someone's name. The @ leapt out at him. Rare, unused, and on top of that it already meant "at". Perfect for separating the person from their machine.

The user@machine format was born, and it has not budged an inch since. The first message ever sent between two computers sitting side by side in the same room? Tomlinson himself admitted he had completely forgotten it, probably a random string of letters. There you have one of the great paradoxes in the history of technology: the founding gesture was so ordinary that its author did not even bother to remember it.

Snail, little monkey and cat's tail

The tastiest part is the way each language looked at this little whirl and saw an animal. The Italians call it chiocciola, the snail, because of its spiral. The Dutch say apenstaartje, the little monkey's tail. In German people long called it Klammeraffe, the monkey clinging to the branches. The Finns see a cat's tail, kissanhäntä. Danes and Swedes prefer the elephant's trunk, snabel-a. The Greeks find a duckling in it, and in Israel it got nicknamed shtrudel, the rolled-up pastry.

You, quiz lover, keep this card up your sleeve: ask around the table what "at sign" is called in Italian. Nine people out of ten will hunt for some learned word, and nobody will think of the snail. French took the serious road with arobase, though "little snail" would have had so much more charm on our keyboards.

There is something cheering in all this. A symbol born to count amphorae of wine, forgotten for decades, brought back to life by chance one day in 1971, and now stared at by half the planet who see a snail or a cat's tail. Next time you type your email address, spare it a thought. It has earned one.