From ARPANET to the World Wide Web: Through Time

The internet is a network of networks that grew from the ARPANET of 1969. The web is one of its services: pages with links, devised by Tim Berners-Lee at CERN.

The internet and the web

These two words are often used as one, but they are different things. The internet is a network of networks: billions of computers joined by wires, optical fiber and radio waves, and the rules by which they exchange data. The web is one of the services that run over that network: pages joined by links, and the programs called browsers that show them.

Compare it with roads and transport. Roads exist on their own, and you can carry anything along them. The internet is the roads. A bread truck, a taxi and an ambulance drive on the same roads, but they are different services. Email, a video call and an online game are services of the same kind, and none of them is the web. The web is the “little pages with links” service.

That is why the web and the internet have different biographies, and the internet came first.

Check yourself: why are email and a video call not the web?

They run over the internet, but they have their own rules and their own programs. The web is only pages joined by links, and the browsers that show them.

First the network: the ARPANET

In the late 1960s, universities and laboratories in the United States used expensive, powerful computers, and everyone had to travel to “their” machine. The agency then in charge of defense research (ARPA) decided to join the computers in a network, so that people could work on any of them from afar.

On 29 October 1969, two computers, one at the University of California, Los Angeles and another at the Stanford Research Institute, were connected for the first time. They wanted to send the word login. The system crashed after two letters, and the first message in the network’s history was “lo”. By December the network had four nodes.

The key idea of the network: data is cut into small packets, and each goes its own way. This was invented independently in the early 1960s by Paul Baran in the United States and Donald Davies in Britain. In the next lesson we’ll see how it works.

Then things went step by step:

1971. Ray Tomlinson sends the first email across a network.
1983. On 1 January the network moves from its old protocol, NCP, to one common set of rules for exchanging data, TCP/IP (we’ll cover it in the third lesson of this part). In the same year the domain name system, DNS, is invented.
1990. The ARPANET is shut down. The network has grown and spread into many networks joined to one another. That is the internet.

By then scientists had email and newsgroups, but no way to simply put a document on the network and give a link to it.

Check yourself: which protocol did the network use before 1983?

A simpler protocol called NCP. From 1 January 1983 the network moved to TCP/IP.

Then the web: CERN

At the European Organization for Nuclear Research, CERN, thousands of scientists worked with all kinds of computers. Documents lay on different machines in different formats, and finding someone else’s work was hard. In March 1989 a British programmer, Tim Berners-Lee, proposed to CERN’s management a system in which documents are joined by links, and you can reach any of them by opening its address. He called the proposal “Information Management”.

The idea was born from joining two long-known things: hypertext (text with links) and the network. To make it real, Berners-Lee devised four parts:

URL: an address by which a document can be found.
HTTP: the rules by which a program asks for a document and a server hands it over.
HTML: the language in which a document is marked up: where the heading, the paragraph and the link are.
A browser and a server: a program that shows a page, and a program that stores and serves it.

By December 1990 the first web server, the first browser and the first page were running at CERN. The first site’s address, info.cern.ch, still exists. On 6 August 1991 Berners-Lee announced the project in a newsgroup, and the first servers appeared outside CERN.

Check yourself: which four parts did Berners-Lee devise?

The URL (the address), HTTP (the rules of exchange), HTML (the markup language), and a pair made of a browser and a server.

Why the first websites were text with links

The first browser showed text and links. Pictures weren’t built into pages then, because the task was different: to link documents. A scientist needed a link to someone else’s paper, not a pretty cover.

After that two things happened, and both mattered:

In 1993 the American developers Marc Andreessen and Eric Bina released the Mosaic browser, in which pictures stood right in the text. It was easy to install, and people other than scientists began to install it.
On 30 April 1993 CERN announced that the web was free and put its code in the public domain. Nobody became the owner of the web, and anyone could build sites and browsers with no licenses and no fees.

That openness explains why the web grew so fast. After that came Netscape, then the browser wars and the dot-com bubble: that is the topic of the next lesson.

For now, test how well you tell the internet from the web. Press to say which one each event belongs to.

Which of these is the internet, and which is the web

1969. The first connection between computers at the University of California, Los Angeles and the Stanford Research Institute (the ARPANET)
1971. Ray Tomlinson sends the first email over the network
1983. The network switches to the TCP/IP protocols
1983. The domain name system (DNS) is invented
1989. Tim Berners-Lee writes the proposal “Information Management: A Proposal” at CERN
1990. At CERN the first web server, the first browser and the first page are running
1993. The Mosaic browser comes out, with pictures in the text
1993. CERN announces that the web is free and its code is in the public domain

Answered: 0 of 8. Correct: 0.

Practice

Your site in the first era. Make it the way it was made in 1991: a heading, a paragraph and a list of links to the sections. The names of the sections are written in the brief you filled in in part 0. Don’t add anything else: no pictures, no video.

If you feel like adding some beauty, wait: in a few lessons you’ll see why sites needed styles.

What was wrong with 1991

A page with only text and links is readable today, and it opens instantly. That is not a flaw. But the first pages had no search and no way to control the look: every browser showed the text in its own way, and the author of a page could do nothing about it. Both flaws brought the next steps to life: search engines and styles.

From ARPANET to the World Wide Web

The internet and the web

First the network: the ARPANET

Then the web: CERN

Why the first websites were text with links

Practice

What was wrong with 1991

Test

Cards

Sources

Videos

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