Papers in PDF format

multiple hierarchy charts have to be created to cover different parts of the web site, user benefits from well-designed
charts used as navigation tools are worth the effort it takes to create them. Examples of multiple hierarchy charts as
navigation tools appear as the "roadmaps" in the 1995 NCAR Annual Scientific Report at
http://www.ncar.ucar.edu/archives/asr/ASR95/ASR95home.html [NCAR staff 1996].
You can add value to a clickable chart by highlighting the title of the last document the user visited before coming to the
chart. This "where-am-I" feature provides additional orientation cues for users. An example of this feature appears
throughout the NCAR Graphics interactive documentation at
http://ngwww.ucar.edu/ngdoc/ng4.0.1/nggenrl/ngroadpg.html [NCAR Graphics Group 1996].
Grid Charts Can Add Value
If the organization of your site resolves to a grid or a table, you can create a grid image map to allow users to navigate
by pointing and clicking on the titles in the grid. Grid charts provide many of the same advantages as hierarchy charts.
Other Kinds of Images Must Be Simple
Image mapping offers a wide range of possibilities for creative navigation tools. Unfortunately, it also offers an equally
wide range of possibilities for confusion. The image must make clear which areas are linked to other files and which
areas are not. The linked areas must also clearly indicate where the link leads; this can be extremely difficult unless you
know that everyone in your audience thinks just like the image designer. Factors such as cultural conditioning, color
blindness, and different perceptual styles can frustrate the most valiant attempts to develop an "intuitive" image. An
example of an intuitive image map is a geographical map that shows political boundaries; the area within each boundary
is mapped to information about that political entity.
Search Engines Need Introductions
Many sites are providing a search engine to help users find information in their site. While this idea is admirable, the
search engine must be implemented in a user-friendly way. Many sites provide insufficient introduction to the purpose
and content of the site. Some sites even greet users with a statement like "This site is searchable. Type a keyword in the
box." The user never received a proper introduction and is now facing an empty box.
Many different search strategies are arising in response to the evolution of search engine technology. So the user
introduction should also provide concise, helpful information about how to get results from your search engine. Linda
Barlow of Monash Information Services publishes an excellent and informative resource to help you understand search
engines at http://www.monash.com/spidap.html [Barlow 1996].
Indexes Have a Long Way to Go
Hypertext indexes are still rare. Some are nothing more than an alphabetized collection of all the links at the web site.
Users who are very patient or very desperate might use such an index, but this is not a user-friendly navigation tool. A
well-developed index--one that simulates what you would see in a high-quality printed book--can actually help users
learn about the information at a web site. The index entries and the entries indented below them can provide useful
insights about the content of the web site, especially if a variety of keywords have been indexed for each of the most
important concepts. But hypertext indexes designed like print-media indexes are extremely rare. This is probably
because they are difficult to develop and and even harder to maintain as web sites evolve. But such indexes would be a
welcome addition to a suite of effective navigation tools.
References
Lynch, P. J. (1995). Web Style Manual. New Haven, CT: Yale Center for Advanced Instructional Media.
http://info.med.yale.edu/caim/stylemanual/M_I_2A.HTML
Horton, W. K. (1994). Designing and Writing Online Documentation, 2nd Edition. New York: Wiley.
http://www.horton.com/brochure/dwold.htm