Deep Dives · June 3rd, 2025
It is a humid summer night in 1971 inside the offices of Bolt, Beranek & Newman. Two refrigerator-sized PDP-10 computers blink in the half-light.
Ray Tomlinson is supposed to be improving CPYNET, a file-transfer tool for ARPANET. Boredom nudges him off script. He wonders: What if I could leave a note on the second computer instead of just shipping files? The question is so small it almost slips past him. History, however, has a taste for small questions.
Tomlinson - soft-spoken contractor, chronic tinkerer - leans across a console and types a single line:
QWERTYUIOP
He presses SEND. On another machine, meters away, the characters arrive. No trumpet sound, no memo, no press release - yet in that moment the world receives its very first networked email.
To tell the machines where to deliver a message he needs a separator - user here, host there. Slashes and colons are already taken. But the @ sign is just sitting there on every ASR-33 keyboard, a symbol that merchants have used for centuries to mean “at the rate of” (think 7 widgets @ $1). Its roots go deeper still - medieval scribes scratched it as shorthand for the Latin "ad", meaning “toward/at.” In other words, the glyph was literally born to connect things.
Read further:
A brief but complete history of
the @ sign
It’s quirky, pronounceable, and - as far as computer syntax goes - totally unemployed. Tomlinson taps it, shrugs, and ships. Half a century later, billions of inboxes still bow to that casual midnight decision.
Within months, informal guidelines began circulating. In 1973 they congealed into RFC 561, and the snowball kept rolling: SMTP in 1982, MIME in 1992, DMARC in 2015-layer upon layer over the original late-night hack.
Year | Milestone | Daily email volume * |
---|---|---|
1973 | First ARPANET mail header standard | < 100 |
1986 | .com addresses top 100,000 | 1 million |
1996 | Hotmail launches webmail | 10 billion |
2004 | Gmail introduces threaded view | 36 billion |
2025 | Global email crosses 347 billion | 347 billion |
* Approximate, pieced together from industry studies and vendor telemetry.
Behind the numbers hides a simple truth: email succeeded not because it was perfect, but because it was good enough and open to everyone. Any computer that could speak the protocol joined the conversation. In an industry addicted to proprietary kingdoms, that openness became email's moat.
Technical debt, yes - but also they’re daily reminders that the modern inbox sits atop half a century of quick wins and clever hacks and that ideas born in a lab at 2 a.m. can outlive their creators.
Tomlinson later admitted he can't swear that the top-row keystroke was the first message; it might have been gibberish, or "TEST." Historians hunted for logs and found none. Yet the myth survives because it captures the casual spirit of the moment: the world shifted before anyone realised it had.
The tech world has tried for decades to kill the inbox - group chat, social DMs, collaboration hubs, you name it. Yet the “Send” button keeps winning bar - bets because it solves more edge-cases than its rivals even attempt. A few of the big reasons:
Until another medium checks all of those boxes at once - and does so without locking users inside one corporation’s walled garden - email will keep outrunning every “email killer” headline.
Send an email today and you’re leaning on a half-century chain of midnight hacks, last-minute glyph choices, and accidental standards. That chain reminds us:
So, the next time you hover over the Send button - whether it’s a launch announcement or a “hey, lunch?” ping - remember you’re contributing to a living archaeological layer. Write like someone might dig it up in 50 years.