KCL • CCH • Minor programme • AV1000 • Electronic communications and publishing

AV1000
Fundamentals of the digital humanities
The Internet and WWW: basic concepts & terms

I. Review of the internet

  1. It's a world-wide system of interconnected nodes.
  2. A node is a computer or a cluster of computers within a single institution (e.g. King's College London).
  3. Each node is independent of all others. The system as a whole is acentric and asynchronous.
  4. Information is exchanged between the sending node and the recipient node through a variable, dynamically determined path consisting of intermediate nodes and their interconnections.
  5. Access to the Internet is obtained from an Internet service provider (ISP), of which King's is one.
  6. Principal uses of the Internet are for electronic mail (via Outlook, Thunderbird, PINE, Simeon, Eudora, etc.), file-transfer (via SSH, FTP, etc.), remote login (via Telnet, SSH, etc.), and the Web (via Firefox, Internet Explorer, etc.). But the network is designed to permit new uses; there isn't a closed list of applications.

II. Client-Server architecture

  1. In an exchange of information between computers, the one requesting information or action is the client, the one supplying the information or taking action is the server.
  2. Any computer on the Internet can be both client and server, but usually the computer you use directly is a client only and servers are usually remote machines.

III. World Wide Web basics

  1. World Wide Web (or WWW) is in essence an electronic publishing and distribution mechanism.
  2. It is an application of the Internet used to distribute units of information called pages.
  3. Each page usually consists of both text and images together with metatextual declarations and formatting instructions written in the Hyper-Text Markup Language (HTML).
  4. Related pages are normally connected together by means of HTML hyperlinks, which cause the referenced page to be displayed when you click on the link; a set of such pages is known as a Web-site.
  5. Effective Web pages combine skills of both content and design. A successful design recognises the characteristics of the electronic medium and takes advantage of them rather than attempts to imitate print publication.
  6. A page may consist of text, graphics (including photographic images and animations), sound, links to other pages and on occasion programming code for specialised actions.
  7. Pages are composed offline, using one of many programs. A specialized program is not necessary: a simple text-editor will suffice. They must then be uploaded to an existing Web site. Once there they may be viewed from anywhere in the world.
  8. The viewing software is called a browser. The most popular browsers are Internet Explorer and Firefox. Both are provided free of charge.
  9. When a browser accesses a page, the server sends it the mixture of text and metatext that the author of the page has composed and uploaded. The browser then interprets the metatextual declarations and instructions, assembling any referenced parts (such as images, which are in separate files) from their source location(s). It then produces the resulting effects on your screen. How the page appears is always to some degree a function of the settings in the browser.
  10. Images tend significantly to increase the amount of time required to download a page to the reader. Therefore it is wise to keep images and image-size to a reasonable minimum.
  11. Because your potential audience may consist of individuals who do not have equipment as up-to-date as your own, and some of whom may be blind or visually impaired, it is also wise to provide the essential information in a way accessible in a text-only environment.

IV. Web addressing

Each page, once it is online, has an address or Uniform Resource Locator (URL). URLs consist of a scheme, followed by the domain name of the Web server software, followed by the path, followed by the filename of the page, thus:

http://www.kcl.ac.uk/humanities/cch/seminars.html where

The last element in the URL may usually be omitted if it is index.html—which is typically assumed if nothing follows the last forward slash (virgule). Some servers use a different default filename. If the default file doesn't exist in a folder you may be able to see a list of the folder contents in your browser.

Domain names are dynamically translated to IP addresses of the form “137.73.2.2”; IP addresses may be used in URLs as well but it is rarely useful to do this. Two online utilities for translation between the two forms are at hcidata.info and centralops.net.

V. Further reading

revised October 2007