lecture 1: hypertext

For a detailed discussion of hypertext, see chapter 3 of the printed course booklet.

The difference between traditional, or "linear" text, and hypertext, has been suggested to be like the difference between hearing and sight: or, between reading a sentence and looking at a picture. You are reading this paragraph in a very specific order (left to right, from the top line down) and it only makes sense when read in that order. It's the same with hearing words read out loud, or indeed any sequence of sounds.

However, compare that with how you absorb this picture of a (pretty decent) sunset:

Your eye jumps from place to place when registering the picture. There's no fixed order in which you can absorb it. You can also look at certain points for longer, to get more detail - pictures have depth as well as height and width. This is how you absorb information about any location in which you're stood (try it now with the room around you).

Presenting information on the WWW, therefore, requires a different approach to presenting it in printed form (as a book, letter, essay or whatever). In those formats there are definite start and end points and the book (essay, letter) is relatively self-contained. A web site, however, is made up of "chunks" which may not get read in the same order each time; some chunks may not get used at all. They are what is known as non-sequential. At a very simple level, each of these "chunks" is a web page and hypertext links are used to join them together into the World Wide Web. Hypertexts are not therefore self-contained, but can in principle be linked to any other online text by a series of "jumps".