Nearly 50 years ago – sometime during the northern summer or autumn of 1971 – Ray Tomlinson sent the first network email. He didn’t invent electronic messaging, but he’s the person who came up with the name@host convention now used by billions of people every day: it was his idea to use the asperand, the @ symbol, as a separator.
Tomlinson was a computer scientist working for Bolt, Beranek and Newman (BBN), a company based in Cambridge, Massachusetts, which started out specialising in acoustics – one of its first big jobs was in acoustics consulting for the new United Nations buildings in New York City.
To aid in its acoustics work, the company invested heavily in computer technology. When the US government, through the Department of Defence, launched its Advanced Research Projects Agency (ARPA, formed in 1958 – in 1972 it added ‘Defense’ to its name, becoming DARPA), and then the Advanced Research Projects Agency Network (ARPANET) in the late 1960s, aimed to link computers at research institutions over telephone lines, BBN was brought in as a consultant and contractor.
Tomlinson was born on 23 April 1941 in Amsterdam, in northern New York state. In 1964 he earned a degree in electrical engineering from the prestigious Rensselaer Polytechnic Institute, and in 1965 he received a master’s degree from the Massachusetts Institute of Technology, where he worked with a group developing an analog-digital hybrid speech synthesiser.
In 1967, while studying for a PhD, he joined BBN (in 2009, BBN was taken over by tech giant Raytheon as a wholly owned subsidiary), in Cambridge, and worked there until his death on 5 March 2016.
Tomlinson wrote an article for a Raytheon BBN Technologies newsletter in which he says that during the summer and autumn of 1971, he “was part of a small group of programmers who were developing a time-sharing system called TENEX that ran on Digital PDP-10 computers”.
An article published by New York’s Columbia University for a computing history series calls the Digital Equipment Corporation’s PDP-10 “one of the most influential computers in history in more ways than can be listed here”.
From 1964 to 1983, it says: “It was the first widely used time-sharing system. It was the basis of the ARPANET (now internet). It was the platform upon which many of today’s popular applications were first developed.”
Tomlinson says he had been working on the Network Control Protocol (NCP) for TENEX and network programs such as an experimental file transfer program called CPYNET.
He says he’d been making improvements to a local inter-user mail program called SNDMSG: “Single-computer electronic mail had existed since at least the early 1960s and SNDMSG was an example of that.”
SNDMSG, he explains, allowed a user to compose, address and send a message to other users’ mailboxes. “A mailbox was simply a file with a particular name. Its only special property was its protection, which only allowed other users to append to the file. That is, they could write more material onto the end of the mailbox, but they couldn’t read or overwrite what was already there.”
Tomlinson says the idea occurred to him that CPYNET, “could append material to a mailbox file just as readily as SNDMSG could. SNDMSG could easily incorporate the code from CPYNET and direct messages through a network connection to remote mailboxes in addition to appending messages to local mailbox files.”
He says the “missing piece was that the experimental CPYNET protocol had no provision for appending to a file; it could just send and receive files. Adding the missing piece was a no-brainer – just a minor addition to the protocol.”
Another article published by Raytheon Technologies describes Tomlinson’s email breakthrough.
It says he had spent hours “trying fruitlessly to get a message from one cabinet-sized computer to another”.
“Now he tried again, banging out his name on a teletype keyboard: TOMLINSON. He followed that with an @ symbol – a little-used key he had chosen as a separator – and then the name of the other computer.
“Tomlinson rolled his chair over to the second computer’s teletype and banged out TYPE MAILBOX on the keyboard.
“For a moment there was silence. And then with a rattle, the teletype came alive. History’s first email had arrived.”
The Raytheon article says that in his induction speech Tomlinson said the invention of email “…‘came out of a personal desire for a more convenient and functional way to communicate. Basically, I was looking for a method that did not require the person to be there when the message was sent and enabled the receiver to read and answer communications at their convenience.’”
In his speech, Tomlinson said he was often asked of his email creation – did he know what he was doing? “‘Yeah. I knew exactly what I was doing. I just had no notion whatsoever about what the ultimate impact would be.’”
His first email traveled only 100 yards – from a computer known as BBN-TENEXB to a router elsewhere in the building, then back to the second computer, BBN-TENEXA. But it was the first time a message had travelled between completely different computers on the ARPANET, the predecessor of the internet.
The achievement seemed so routine that not even Tomlinson could remember the exact day it happened, or even the content of the message. “‘Every time I tested, I typed in something – testing 123 or something innocuous like that – and then I would send it and see what happened.’”
After dozens of tries, one message came through. “‘There was nothing momentous about it.’”