Email inventor Ray Tomlinson has passed into the eternal computer network in the sky, after a suspected heart attack at the age of 74.

Ray Tomlinson – image via Flickr

An American computer programmer, Tomlinson implemented the first email system on ARPANET, the first network to implement the protocol suite TCP/IP and the primary precursor to the internet; although the concept of sending electronic mail itself came before Tomlinson, prior to his work messages could only be sent to users who used the same computer.

Tomlinson’s solution to sending what became known as email across ARPANET was an address system which utilized the @ symbol (at symbol) to allow the message to be routed to a person in the combination of username @ machine name, or as we now know at, at a domain name.

As he explained in a blog post:

I was making improvements to the local inter-user mail program called SNDMSG. Single-computer electronic mail had existed since at least the early 1960’s and SNDMSG was an example of that. SNDMSG allowed a user to compose, address, and send a message to other users’ mailboxes.

A mailbox was simply a file with a particular name. It’s 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. The idea occurred to me 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.

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. I don’t recall the protocol details, but appending to a file was the same as writing to a file except for the mode in which the file was opened.

Next, the CPYNET code was incorporated into SNDMSG. It remained to provide a way to distinguish local mail from network mail. 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.

Champion

Tomlinson was inducted into the Internet Hall of Fame in 2012, where his citation reads:

Tomlinson’s email program brought about a complete revolution, fundamentally changing the way people communicate, including the way businesses, from huge corporations to tiny mom-and-pop shops, operate and the way millions of people shop, bank, and keep in touch with friends and family, whether they are across town or across oceans. Today, tens of millions of email-enabled devices are in use every day. Email remains the most popular application, with over a billion and a half users spanning the globe and communicating across the traditional barriers of time and space.

While there are quite a few people who can be credited with the internet as we know today, Tomlinson, along with the likes of Vince Cerf, who took Tomlinson’s invention of email and gave it to the masses, along with Sir Tim Berners-Lee, the inventor of the world wide web, stand tall as the people who have shaped not only the digital revolution, but our futures as well, for without such great men, we may never have progressed to the point we have today.

RIP Ray Tomlinson 1941-2016.

Image credit: dskley/Flickr/CC by 2.0