The Companion encyclopedia articles have 3 types of navigation tools, none of which are under the control of the authors.
- These are used by the editors to list articles related
(in subject matter) to an article, by the authors to give "a sense of what needs to be treated" in their article as well as what will be covered in other articles.
On Wikipedia, this is akin to a category listing except there is no ability to cross-reference all the categories an article is a member of (well, there are a few extensions which can do this, but they are not available on wikipedia projects.) More importantly, without any clear editorial oversight articles tend to propagate on a given topic under a half-dozen and more related titles.
- Blind entries
- These are simple entries which redirect readers to entries where the topic is discussed.
It is quite possible redirects on Wikipedia should be categorized in some manner to allow a tree-view of what redirects where in a category format.
- Topical index
- This is the power-house search system of the encyclopedia, though more akin to wikipedia's categories in implementation.
It need hardly be mentioned that Wikipedia's search engine is rather less than optimal, and the usual approach by readers is to use Google minimally complex searches rather than the not-very-useful search system of Mediawiki.
Wikipedia clearly has more and better navigational tools than a dead-tree encyclopedia, but then it lacks the paper-turning options. A primary weakness, however, is the categorization system of Mediawiki which does not present a hierarchical view of categories, necessary for browsing related content. For category views it is likely an ajax-based dynamic breadcrumb navigator (including subcategories of viewed category) is the best option, although this would rely on JS being activated for the client browser.