Ray Tomlinson, the Arpanet contractor who is credited with sending the first email across a network, is no more, but his creation remains the killer app of the internet. It is the one feature which no user can do without. Email came before the internet, some of whose building blocks derive from it, and it could outlast the internet as we know it. Venture capitalists have been dying to invest in the next killer app, but it isn’t happening in their lifetime.
Tomlinson is credited with a tweak to the SNDMSG programme, used for transferring text messages between computers, which enabled it to send messages across a network, and eventually the internet, which is the network of networks. It is generally agreed that he sent the first real email in 1971, though the technology existed earlier, in the form of messages passed between users of a shared computer. There were no distributed networks at the time. Arpanet, on which Tomlinson worked, was the very first, and it offered the first opportunity to mail across a network.
However, Tomlinson didn’t have the familiar inbox, outbox and send button. Emails are just text strings, and the earliest were sent from the command line. In fact, it is still possible to type out and send a mail from a blank command line, but it is a rare form of self-torture. Tomlinson was also responsible for the ubiquity of the @ sign, borrowing from the Unix addressing convention which identifies a user of a host computer as user@host. Tomlinson never tried to take credit for his tweak, and his contribution was not noticed until well after it had changed the way the world communicates. He got no reward for it, and he would have been agreeably surprised to find that today, his passing is being noted the world over.