|VUG Home Page NIST Web Metrics Technical Overview TreeDec Overview|
So-called "breadcrumbs" (as defined in "Designing Web Usability" by Jakob Nielsen) are a feature of webpages that allow the user to see logical context and navigate. Breadcrumbs are really an ancestor path - a list of parent, grandparent, etc. showing the logical subtree in which the current page lives. Decorating all the pages of a website correctly and consistently is a tricky and boring task. Furthermore, the overall tree logically implicit in the paths may not be shown explicitly, even though such an overview might be valuable as a sitemap or table of contents.
All the information necessary for breadcrumb processing can be represented as a single tree structure. The main purpose of TreeDec is to allow website authors and designers to maintain the logical tree structure of their website in a single file and to use that file to control the systematic addition of breadcrumbs to the webpages of the site.
It should be emphasized that the logical organization of the pages of a website into a tree is independent of other organizational structures, in particular:
Finally, if the location of a webpage in the logical tree is important, then perhaps the user would want to see not only ancestors, but other nearby nodes, namely siblings and children. Thus the user can go anywhere within the immediate vicinity of the current page. Since this information is implicit in the tree structure anyway, sibling and child links are available as options.
For a more detailed overview of TreeDec, see this article.
The TreeDec system includes pre-processing utility programs called td-convert-ll and GenTree to help the website developer create a file representing the tree structure. TreeDec itself accepts as input the tree file (however created) and applies it to the website. The result is a consistent labelling of all the webpages, plus an HTML skeleton of the hierarchy to be used as a table of contents. Here is an example of the output of TreeDec: the root page and table of contents of a geography oriented decorated website (with no actual content).
||TreeDec is a tool in the Web Metrics Testbed developed at NIST. For more information, see http://www.nist.gov/webmetrics. Direct all comments and questions to firstname.lastname@example.org. Before using this tool, please review the TreeDec release notes and known bugs.|
Page last modified: 15 May 2002
National Institute of Standards and Technology (NIST)