The Birth of Modern Email: Ray Tomlinson’s Groundbreaking Moment
In late 1971, Ray Tomlinson sat in a beige office at Bolt Beranek and Newman (BBN) in Cambridge, Massachusetts, facing two massive refrigerator-sized mainframes. These machines were connected to ARPANET, the pioneering Pentagon-funded network that would later evolve into the internet. Tomlinson wasn’t working on email per se; rather, as his employer’s spokeswoman later described, he was just fooling around with a file-transfer program combined with a local messaging tool, curious about the potential of merging the two functionalities.
He typed a string of characters on one machine, addressed the message to himself on the other, and pressed send. The message traversed ARPANET, a distance of roughly fifteen feet, and appeared on the second machine. The content was, by Tomlinson’s admission, entirely forgettable—most likely a sequence like QWERTYUIOP, the letters across the top row of his keyboard.
To link the username with the destination machine, Tomlinson reached for a character that was unique and unambiguous, one that could never be part of a person’s name:
The @ sign.
The Room Where It Happened
Bolt Beranek and Newman, affectionately known as BBN, was a consulting firm heavily involved in Defense Department projects, with a culture resembling a graduate physics lab more than a traditional corporation. Tomlinson had joined BBN in the late 1960s after completing his studies. By 1971, BBN was deeply engaged with ARPANET, and Tomlinson was developing critical low-level system software, including components integral to the network’s infrastructure.
The two mainframes in his office ran multi-user operating systems. Each machine had its own users and a rudimentary local mail program, enabling users on the same machine to leave messages akin to memos in physical mailboxes. However, there was no system in place for sending messages between different machines located miles apart.
Tomlinson was working on a utility to transfer files across ARPANET hosts. He wondered: what if the files being transferred were appended to mailbox files instead of overwriting them? This simple tweak would allow messages to be delivered to mailboxes on remote machines, a breakthrough concept that laid the foundation for network email.
Why the @ Sign?
Creating a networked mail system required a clear separator between the username and the host machine in an address. Tomlinson scanned his keyboard, a clattering electromechanical device printing uppercase letters and symbols, to find a punctuation mark that was never part of usernames.
Most punctuation marks were unsuitable: periods were common in filenames, commas and semicolons separated list items, slashes appeared in paths, and hyphens and underscores were often part of names. The character needed to be unmistakable, something that would never be interpreted as part of a user’s identity.
The @ symbol fit perfectly. As his employer’s spokeswoman later noted, it was a relic of accounting — used by grocers to denote “at a rate of,” such as six apples @ 10 cents each. It had survived into the 20th century mainly because commercial typewriters had included it for bookkeeping purposes since the late 1800s.
Furthermore, the @ symbol elegantly read as the English word “at,” making addresses like tomlinson@bbn-tenexb intuitive. The grammar of the address explained itself instantly, bridging human language and machine logic.
An Old Symbol with a Long, Strange Past
The looping @ shape had been drifting through manuscripts for centuries. Medieval scribes used it for various purposes, and Renaissance merchants in Venice and Florence adopted it as commercial shorthand. The symbol evolved into the “arroba” — a historical Spanish and Portuguese unit of weight — appearing in trade ledgers before making its way onto nineteenth-century American accountant’s typewriter keyboards.
By the time Tomlinson encountered it, the @ symbol had quietly served bookkeeping and commerce for generations. Its adoption for email would transform it into the most widely transmitted piece of punctuation in human history.
What the First Message Actually Was
Tomlinson sent several test messages between the two mainframes during that autumn, but he never recorded them. In later interviews, he described them as forgettable strings of characters intended to verify the program’s functionality, likely a keyboard run such as QWERTYUIOP. There is no surviving record of these initial transmissions.
After confirming the system worked, Tomlinson sent a message to his colleagues at BBN announcing the arrival of network mail and explaining how to address messages across machines. This was the first email anyone other than Tomlinson received, but unfortunately, no copy of this historic note remains.
When reflecting on his invention decades later, Tomlinson famously summed it up with understated humility: he built it simply because it seemed like a neat idea.
From Neat Idea to Global Standard
For its first decade, network email remained confined to the research community. In 1971, ARPANET connected a limited number of host computers spread across universities, defense labs, and contractors like BBN. Only a few hundred users with machine accounts could send messages.
However, the @ character spread faster than the technology itself. Programmers developing other mail tools adopted Tomlinson’s syntax because it was logical and clear. By the mid-1970s, the format user@host had become the de facto standard across ARPANET.
When the Simple Mail Transfer Protocol (SMTP) was formalized in the early 1980s and deployed network-wide, the @ symbol was baked into the standard. Every email address sent since then uses the syntax that Tomlinson improvised in a Cambridge office.
While email’s technical underpinnings evolved repeatedly, the format of the address — the @ sign linking user and host — remained unchanged.
The Character That Came Back from the Dead
Before 1971, the @ sign was so marginal that some European keyboards omitted it entirely; for example, Italian typewriters often shipped without an @ key. After Tomlinson’s innovation, keyboard manufacturers worldwide reinstated the character, giving it a new lease on life.
The symbol’s cultural significance blossomed globally, inspiring unique names in different languages that reflect its curious form. In Italian it is chiocciola (snail), in German Klammeraffe (spider monkey), in Hebrew strudel (pastry), in Czech and Slovak zavináč (rolled pickled herring), and in Greek papaki (little duck). Each culture reached for familiar animals or foods to describe a symbol that had previously been obscure.
None of these metaphors existed before Tomlinson made the character an indispensable part of daily digital communication.
The Engineer Who Was Not Addicted to His Own Invention
Tomlinson remained at BBN for his entire career, still working as a principal scientist when he passed away in March 2016 at age 74. His pioneering role earned him induction into the Internet Hall of Fame, lifetime achievement awards from the Association for Computing Machinery and IEEE, and recognition as one of the 20th century’s most influential engineers.
Despite the global impact of his work, Tomlinson lived quietly in Lincoln, Massachusetts, where he raised miniature sheep. Colleagues remembered him as patient and modest—an engineer who would patiently mentor junior programmers.
His employer’s spokeswoman noted that he was surprisingly not addicted to email himself. Tomlinson never patented his invention or attempted to commercialize it. The technical paper he authored on file transfer protocols mentioned network mail only as an afterthought. To him, it was simply a side project that worked.
What Survives in the Address Bar
The ARPANET network of 1971 had fewer host computers than a modern coffee shop has Wi-Fi clients. The mainframes Tomlinson used weighed nearly a ton, cost hundreds of thousands of dollars, and contained less memory than a contemporary microwave oven. The keyboard he typed on printed in uppercase letters only, at ten characters per second, onto a continuous roll of yellow paper. The first email traveled a distance shorter than a city bus.
Yet, pull up any email address today — whether at a hospital in Lagos, a trading desk in Singapore, a school in São Paulo, or a Mars rover team in Pasadena — and the punctuation that separates user from host is the same @ symbol Tomlinson chose. It was picked because it would never appear inside a person’s name. This forgotten accounting symbol underpins every email login worldwide. Billions of times a day, fingers reach for the same key.
Most punctuation marks clarify sentences. The @ sign clarifies identity and location. It is the only standard keyboard character whose modern purpose is not writing prose but pointing: this name, that machine. A small piece of bookkeeping shorthand, resurrected from obscurity, still serves as the digital world’s indispensable locator.
