WebGuide is a Knowledge Building Environment developed by Gerry Stahl and colleagues at the University of Colorado. The client component of WebGuide runs as a Java applet in a new window of the user's Internet browser. The applet centrally includes a hierarchical tree of information, typically presenting the title of a selection of notes in a threaded discussion. When the user selects a note by clicking on its title with the mouse, the content of that note is displayed in the browser's original window. The advantage of this arrangement is that the hierarchy of titles can be quickly and flexibly manipulated in the Java interface. (An equivalent HTML interface would be awkward and slow.) On the other hand, the note content is displayed in a full-featured HTML window, where fonts, links and graphics can take advantage of the full power of HTML.

The problem with the design of WebGuide is that the user can only view the content of one note at a time. This is clumsy for following the narrative flow of a thread of discussion. It is also inconvenient for printing sequences of notes because printing is restricted to the HTML window.

Our solution was to allow multiple notes to be displayed in the HTML window by using XML technology. Modern browsers (e.g., IE 5.0 and later) support XML. Soon they will support XSL (the associated style sheets for a given XML DTD). A number of selection procedures are either implemented or under development:

a. The user opens certain parts of the hierarchy of note titles and pushes a "print visible" button. For all the notes whose titles are visible in the Java window, their contents are now displayed in the HTML window. The HTML display is properly indented and formatted with the author's name, the title and other related information based on an XSL style sheet. 

b. The user selects a number of contiguous or non-contiguous note titles by holding down the Shift or Control button while clicking on the titles. The "print selected" button is then used.

c. The "print recent" buttons will select and display the contents of all notes added to the KBE within the past N days, where N = 2, 7, or 14.

d. The "search" button will select and display the contents of all notes containing a specified string of words or letters.

e. The "relevant" button will select and display the contents of all notes that are semantically closely related to the selected note. (This function takes advantage of Latent Semantic Analysis.)

The Java and Perl source code for function (a) is available.

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This page last modified on August 01, 2003