Email is much older than ARPANet or the Internet. It was never invented; it evolved from very simple beginnings.
Early email was just a small advance on what we know these days as a file directory - it just put a message in another user's directory in a spot where they could see it when they logged in. Simple as that. Just like leaving a note on someone's desk.
Probably the first email system of this type was MAILBOX, used at Massachusetts Institute of Technology from 1965. Another early program to send messages on the same computer was called SNDMSG.
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Before internetworking began, therefore, email could only be used to send messages to various users of the same computer. Once computers began to talk to each other over networks, however, the problem became a little more complex - We needed to be able to put a message in an envelope and address it. To do this, we needed a means to indicate to whom letters should go that the electronic posties understood - just like the postal system, we needed a way to indicate an address.
This is why Ray Tomlinson is credited with inventing email in 1972. Like many of the Internet inventors, Tomlinson worked for Bolt Beranek and Newman as an ARPANET contractor. He picked the @ symbol from the computer keyboard to denote sending messages from one computer to another. So then, for anyone using Internet standards, it was simply a matter of nominating name-of-the-user@name-of-the-computer. Internet pioneer Jon Postel, who we will hear more of later, was one of the first users of the new system, and is credited with describing it as a "nice hack". It certainly was, and it has lasted to this day.
Despite what the world wide web offers, email remains the most important application of the Internet and the most widely used facility it has. Now more than 600 million people internationally use email.
By 1974 there were hundreds of military users of email because ARPANET eventually encouraged it. Email became the saviour of Arpanet, and caused a radical shift in Arpa's purpose.
Things developed rapidly from there. Larry Roberts invented some email folders for his boss so he could sort his mail, a big advance. In 1975 John Vittal developed some software to organize email. By 1976 email had really taken off, and commercial packages began to appear. Within a couple of years, 75% of all ARPANET traffic was email.
Email took us from Arpanet to the Internet. Here was something that ordinary people all over the world wanted to use.
As Ray Tomlinson observed some years later about email, "any single development is stepping on the heels of the previous one and is so closely followed by the next that most advances are obscured. I think that few individuals will be remembered." That's true - to catalogue all the developments would be a huge task.
One of the first new developments when personal computers came on the scene was "offline readers". Offline readers allowed email users to store their email on their own personal computers, and then read it and prepare replies without actually being connected to the network - sort of like Microsoft Outlook can do today.
This was particularly useful in parts of the world where telephone costs to the nearest email system were expensive. (often this involved international calls in the early days) With connection charges of many dollars a minute, it mattered to be able to prepare a reply without being connected to a telephone, and then get on the network to send it. It was also useful because the "offline" mode allowed for more friendly interfaces. Being connected direct to the host email system in this era of very few standards often resulted in delete keys and backspace keys not working, no capacity for text to "wrap around" on the screen of the users computer, and other such annoyances. Offline readers helped a lot.
The first important email standard was called SMTP, or simple message transfer protocol. SMTP was very simple and is still in use - however, as we will hear later in this series, SMTP was a fairly naïve protocol, and made no attempt to find out whether the person claiming to send a message was the person they purported to be. Forgery was (and still is) very easy in email addresses. These basic flaws in the protocol were later to be exploited by viruses and worms, and by security frauds and spammers forging identities. Some of these problems are still being addressed in 2004.
But as it developed email started to take on some pretty neat features. One of the first good commercial systems was Eudora, developed by Steve Dorner in 1988. Not long after Pegasus mail appeared.
When Internet standards for email began to mature the POP (or Post Office Protocol) servers began to appear as a standard - before that each server was a little different. POP was an important standard to allow users to develop mail systems that would work with each other.
These were the days of per-minute charges for email for individual dialup users. For most people on the Internet in those days email and email discussion groups were the main uses. These were many hundreds of these on a wide variety of topics, and as a body of newsgroups they became known as USENET.
With the World Wide Web, email started to be made available with friendly web interfaces by providers such as Yahoo and Hotmail. Usually this was without charge. Now that email was affordable, everyone wanted at least one email address, and the medium was adopted by not just millions, but hundreds of millions of people.