Ray Tomlinson, the American computer legend who invented the first email system to send messages between users of different hosts, passed away from a suspected heart attack. He was 74.
After joining IBM in 1963 as an intern, Tomlinson went on to earn a master’s degree in electrical engineering from MIT in 1965. Years later he worked at the engineering firm Bolt Beranek and Newman (BBN), where he contributed to the development of the TENEX operating system.
While at BBN in 1971, he was a driving force in the implementation of ARPANET, on which he built the first email application for sending messages across a network. Tomlinson described his first email implementation this way:
The first message was sent between two machines that were literally side by side. The only physical connection they had (aside from the floor they sat on) was through the ARPANET. I sent a number of test messages to myself from one machine to the other. The test messages were entirely forgettable and I have, therefore, forgotten them. Most likely the first message was QWERTYUIOP or something similar. When I was satisfied that the program seemed to work, I sent a message to the rest of my group explaining how to send messages over the network. The first use of network email announced its own existence.
In addition to helping develop common email standards, it was Tomlinson’s idea to use the @ symbol to denote user and host. The influence of the “at sign” can be seen today, where it’s still famously used in email and more recently on Twitter. The symbol’s usage has a long and interesting history starting 480 years ago when it indicated weight and volume, as the New York Times detailed in 2009.
In recent centuries, @ became accounting shorthand for “at the price of,” which led to its inclusion on typewriters and eventually computer keyboards. This is where Ray Tomlinson found the perfect symbol for email. He put it this way on BBN's website:
I chose to append an at sign and the host name to the user's (login) name. I am frequently asked why I chose the at sign, but the at sign just makes sense. The purpose of the at sign (in English) was to indicate a unit price (for example, 10 items @ $1.95). I used the at sign to indicate that the user was "at" some other host rather than being local.
For his many contributions, Ray Tomlinson was inducted into the Internet Hall of Fame in 2012, where his bio is published.