The unplanned uses
The researchers who built the first computer networks expected them to be used for sharing computing power and data. What happened was somewhat different. People found that the most valuable thing a network connected was other people. Many of the effects that now seem ordinary, such as messaging, online groups and shared documents, started in this unplanned way.
Electronic mail
Electronic mail already existed on time-sharing systems, where users of one computer could leave messages for one another. In 1971, Ray Tomlinson, an engineer at BBN, adapted a program so that a message could be sent to a user on a different machine on the ARPANET. He chose the @ symbol to separate the user’s name from the name of the host computer, a convention that survives. In the next few years, programs added features such as replying, forwarding and filing, and mail became one of the most heavily used services on the network. Some accounts say it made up a large share of ARPANET traffic by the mid-1970s.
Mail changed the way research groups worked. People in different cities could discuss problems and send drafts without arranging a phone call or waiting for the post, and they could do so at any hour. Mailing lists, which sent one message to many subscribers, appeared early, and some, such as lists for science fiction fans, were purely social. That suggested that the network could support communities of interest as well as technical collaboration.
Shared files and remote work
The File Transfer Protocol, defined in the early 1970s, allowed users to copy files between computers. Researchers could publish software and data sets for others to download. This became the basis for early open collaboration: programmers shared code, fixed one another’s bugs and passed along improvements. Remote login let people use machines in distant places, which made it less important to live near a particular computer center.
The same habit of sharing led to the public documents describing network standards, which anyone could read and comment on. The culture of open exchange of information in the research networks shaped how later parts of the internet developed.
Discussion groups and bulletin boards
In 1979 and 1980, two graduate students at Duke University, Tom Truscott and Jim Ellis, together with Steve Bellovin at the University of North Carolina, created Usenet. It spread topic-based discussion groups between Unix computers using ordinary telephone connections, so universities without an ARPANET link could take part. Usenet grew to include thousands of sites and became an early example of an online community with its own habits and arguments, including complaints about newcomers and off-topic posts.
Meanwhile, people with personal computers and modems started running bulletin board systems. One of the best known, the Computerized Bulletin Board System, was set up in Chicago in 1978 by Ward Christensen and Randy Suess. A bulletin board was a home computer that other people could dial into to leave messages and download files. Commercial services such as CompuServe offered access to subscribers for a fee. The Well, an online community in California, started in 1985, and France’s Minitel system, begun in 1982, provided other versions of the same idea. All of this took place before the public internet.
Economic effects
Connected computers began to change business in several ways. Banks and airlines used networks to run reservations and transactions from a distance. Automated teller machines, linked to a bank’s central computer, made it possible to withdraw cash away from a branch. In the 1980s, companies exchanged purchase orders and invoices through electronic data interchange, which replaced paper forms. Once the web and commercial providers arrived in the 1990s, online shopping, advertising and services started to grow and new kinds of companies appeared, followed by a stock market boom and a sharp fall around 2000.
Networks also made it easier to divide work across distance. Companies could place staff, call centers or suppliers in different regions, and software could be built by teams spread across time zones. Some jobs changed or disappeared, and new jobs appeared; economists continue to debate the net effects, and they differ by place and period.
New problems
Connectivity also brought difficulties. Unwanted bulk mail, later called spam, was noticed on ARPANET in 1978, when a message was sent to a large number of users and drew complaints. Online arguments, harassment and misinformation have older roots than social media. Access was unequal, since early networks were mostly open to universities, the military and technical workers, and later, to those who could afford computers and phone lines, which created what is often called a digital divide. Privacy and security concerns grew as more personal information moved online.
Looking back
Calling these changes a revolution is a judgment rather than a fact, and it can hide the slow pace of the early years. For a long time, only specialists took part. But the main pattern is clear: whenever computers were connected, people used the links first for conversation and sharing, and the technology followed their habits. That pattern repeated with the web, with social media and with mobile messaging.