« Chapter 1 ⌂ Home Chapter 3 »
Chapter 2 — The History of the Internet and the World Wide Web
from Evaluation of Human-Computer Interaction Whilst Using the World Wide Web
by Nicolas J. Blaza  ·  The Buckinghamshire College, a college of Brunel University  ·  May 1996

2.1 Introduction to the Internet

The Internet was born 20 years ago. The US Department of Defence was afraid that its strategically important military defence computer network could be "blinded" by a Russian bomb. Computer networks in those days were very rigid, hierarchical structures. At the top of every computer network was a central computer, which would co-ordinate the activities of all other computers connected to it. If one computer wanted to talk to another, it would need to get clearance from the central computer. This type of network was vulnerable to attack — one bomb could effectively wipe out a whole network. The Advanced Research Projects Administration (ARPA) was set up to design a new network model that could withstand such an attack. The result was known as the ARPANet.

ARPANet was designed around the principle of "unreliable computers". That is, it had to be able to withstand the destruction of one or more computers, but still allow the other computers to communicate effectively. The network was designed so that each computer on the network was charged with the responsibility of ensuring that its communications were successfully carried out. Each computer knew where every other computer linked to the network was, by the use of unique addresses stored on a distributed database, which painted an overall network map.

Every computer was regarded as equal to every other computer, so it did not require permission to talk with other computers. Most importantly, it assumed that every other computer was "unreliable" — that it might fail at any time — and probed them at regular intervals to ensure the lines were still open. If a computer was down, it would note that on its "map" and not use that computer when passing on information until the situation had been rectified.

The design was quite successful. Central to the design was the TCP/IP (Transmission Control Protocol / Internet Protocol) software, which regulated how the computers would interact with each other.

The network was used to link the military's computers, as well as a small number of academic sites (to allow for further study of the networking principles). The ARPANet began to grow, with more and more sites wanting to gain access to it, linking most US universities, and even some UK and other European computers. The flexibility of the ARPANet working environment was very attractive to governments and academic groups worldwide. Providing a computer could understand and implement the networking protocols upon which ARPANet was based, it could talk to any other computer that could understand that protocol. This was seen as a cheap and practical means of connecting different types of computers to share information (Krol, 1994).

2.2 What Does Each Part of an Internet Address Mean?

Here are the components of an Internet address "aname@aserver.com":

Addresses use lowercase letters without any spaces. The name of a location contains at least a string and, typically, a three-letter suffix, set apart by a dot. The name of a location might require several subparts to identify the server (a host name and zero or more sub-domains), each separated by dots. For example, the address aname@aserver.bserver.com uses a sub-domain.

The three-letter suffix in the location name helps identify the kind of organisation operating the server. (Some locations use a two-letter geographical suffix.) Here are the common suffixes and organisational affiliations:

Email addresses from outside the United States often use a two-letter suffix designating a country. Here are some examples:

2.3 How Big is the Internet?

An American company called Network Wizards has tried to answer this question by a complete search of the Domain Name System. The results are published on the World Wide Web at http://www.nw.com. The latest figures from July 1995 found that there are 6.642 million hosts with 120,000 domains. Network Wizards analysed the three-letter Internet domains, shown above, to try to determine world-wide use of them. The commercial .com domain is found in 54 countries; the .net domain used by network service providers is in use in 57 countries; while 27 countries and most UN agencies make use of the .org (organisation) domain; and 16 countries use the .edu (educational) domain (Network Wizards Web page, 1995).

The top ten number of Internet hosts by country are:

[Original table of host counts per country has not been reliably reconstructed from the OCR.]

2.4 The World Wide Web

The easiest way to access the Internet is via the World Wide Web (Web or W.W.W). It is one of the most recent developments on the Internet. It takes what was previously an unwieldy collection of archaic commands and text-based menus, and presents the Internet in a graphical user interface environment (GUI).

Because of its ease of use, the W.W.W has caught the imagination of the mass media, technologists, educators and even big business. "The W.W.W is the computer application that will bring the masses to the Internet" (Gates, 1995).

2.5 Hypertext

The W.W.W has evolved around the concept of hypertext. Web documents are created by authors using a language called HTML (HyperText Markup Language) that offers short codes (also called tags) to designate graphical elements and links. Clicking on links brings documents located on a server to a browser, irrespective of the server's geographic location. Documents may contain text, images, sounds, movies, or a combination. (When different media are included in the hypertext system, the result is termed "hypermedia".)

Hypertext is a software-based tool that enables text to be displayed in a manner that emulates the human thought processes. Usually when text is displayed, either electronically or on paper, the reader has to read each page sequentially, or manually skip sections not relevant to them. The human brain does not always want to receive information sequentially; individual words or concepts may attract attention. Occasionally the reader may continue to read through the text, but more likely will want to move on and read the connected passage.

Hypertext documents are associative, not linear. This is achieved by incorporating links in texts that enable users to jump to another part of the document that contains relevant information and then return to where they left off. Keywords are linked to other parts of the document, or even other sites on the W.W.W. These key words are displayed on screen in a different colour, italicised or underlined, allowing them to be readily identified by the user.

2.6 Viewing Documents on the W.W.W.

The World Wide Web is one facet of the Internet, consisting of client and server computers handling multimedia documents. Client computers use browser software (such as Netscape Navigator) to view documents (pages). Server computers use server software to maintain documents for clients to access.

Hypertext links are contained in documents, and the software used to view them are called browsers. A Web browser is a software application that can interpret the links embedded in the documents and access the related documents upon demand. On plain hypertext systems, all the documents linked to each other are usually on the same machine. When this software has access to the connectivity of the Internet, it brings into play a whole new realm of information retrieval.

W.W.W. documents often contain links that automatically connect the reader to machines on different parts of the Internet, even on the other side of the globe. The connection happens seamlessly in the background. Users are not required to know the commands necessary to make a connection, or how to retrieve the file and download it. This represents a very powerful tool for accessing information. "It will allow even the computer illiterate to make full use of the Internet" (Heslop and Angell, 1994).

2.7 Accessing the Web

Users install the client software, i.e. Web browsers, to connect to Web servers. There are thousands of Web servers around the world, containing hundreds of gigabytes of information, software, graphics, etc. There are also several Web servers dedicated to providing such a search facility to help users track down information via the W.W.W. All of which makes the users' lives much easier.

2.8 What's the Web Used For?

The Graphics, Visualization, & Usability Center (GVU) at the Georgia Institute of Technology, USA (http://www.cc.gatech.edu/gvu/user_surveys/) conduct a bi-annual survey of the demographics of Web users and what people use the Web for. The third survey ran from April 10th to May 10th 1995, and over 13,000 unique responses were collected. GVU conclude that the most common use of the Web is for browsing (82.6%), followed by entertainment (56%) and work (50.9%). The category that had the least responses was shopping, with 10.5%.

The Graphics, Visualization, & Usability Center also asked the question "What do people do with their Web browser and with what regularity?" and asked respondents to place a score between 0 (for never) and 9 (for regular). The most popular activity for using a Web browser was to replace other Web browsers such as FTP (file transfer protocol), Gopher, etc. (6.7). Other categories included accessing reference material (6.2), electronic news (5.7) and product information (5.1). GVU conclude by suggesting that this supports the notion that Web browsers are becoming the default interface to the Internet. (The results of the fourth survey are expected in mid-June 1996.)

« Chapter 1 ⌂ Home Chapter 3 »

© 1996 Nicolas J. Blaza. Reconstructed online edition, 2026.
Best viewed in Netscape Navigator 2.0 or higher at 800×600 resolution.

The Buckinghamshire College