The @ sign

It’s the @ symbol on the computer keyboard, which is an essential component of every e-mail address.
No one knows for sure when it first appeared.
One suggestion is that it dates to the sixth or seventh century when it was adopted as an abbreviation of “ad,” the Latin word for “at” or “toward.”
Another theory is that it was introduced in 16th-century Venice as shorthand for the “amphora,” a measuring device used by local tradesmen.
The @ appeared on the keyboard of the first typewriter, the American Underwood, in 1885 and was used, mostly in accounting documents, as shorthand for “at the rate of.”

In the U.S. Department of Defense Mr. Tomlinson was responsible for the messaging service. He wrote the addresses in computer code, which needed to be translated into a form of words that the rest of us could understand.
Having decided that the first half of the address should identify the user and the second the computer, he looked for a symbol to indicate that he or she was literally “at” that machine.

The Museum of Modern Art in New York has deemed it to be such an important example of design that the @ has been officially admitted to its architecture and design collection.
How did the @ fare? Brilliantly, according to Ms. Antonelli.

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