Every email you’ve ever sent uses a symbol one engineer picked in 30 seconds. He wasn’t supposed to be building email. When he showed a colleague, the first words were: “Don’t tell anyone. This isn’t what we’re supposed to be working on.”
In 1971, Ray Tomlinson was an engineer at a tech company in Cambridge, Massachusetts that had a government contract to build an early version of the internet. His actual job was writing code to move files between computers. Nobody asked him to build a messaging system. He picked it up as a side project because it “seemed like a neat idea.”
So he needed to figure out addressing. If you’re sending a message from your computer to mine, the system needs to know two things: my name, and which computer I’m on. He needed one character to separate those two pieces. He looked down at his keyboard, an old mechanical terminal called a Teletype where @ sat above the letter P, and ran through his options. Exclamation point was already being used in programming, so that was out. Comma, same problem. Equal sign didn’t make sense. The @ was just sitting there, unused by almost anyone, and it already meant “at” in old pricing shorthand. He picked it and moved on.
The first email went between two computers sitting next to each other in the same room. The message was probably just “QWERTYUIOP,” the top row of the keyboard. He later said the test messages were “entirely forgettable and I have, therefore, forgotten them.” I think it might be the most nonchalant origin story in computing. The guy invented the most used communication format on earth and didn’t even bother to write a real sentence.
Two years later, email made up 75% of all traffic on that early internet. The Pentagon was furious. Defense Department auditors said they’d accidentally built a communication system, which wasn’t their job. They got officially reprimanded for it.
The @ symbol is way older than computers. First known use was in 1536, by a merchant in Florence named Francesco Lapi, writing about wine shipments. He used @ as shorthand for a clay jar used to measure wine. From there it ended up on typewriter keyboards as a pricing notation (“10 apples @ $1 each”), and by 1971 it had been sitting on keyboards for decades while almost nobody touched it.
Today, about 392 billion emails cross the internet every single day. Every one of them carries the @ that one engineer chose during an unauthorized side project 55 years ago, a project he was told to keep quiet about.
The “@” symbol in your email exists because of one engineer’s decision