Subsites - Page 22

Web users need structure to make sense of the many and varied information spaces they navigate. The fundamental nature of the Web does not support any structure beyond the individual page, which is the only recognized unit of information.

Single pages are obviously not sufficient as a structuring mechanism, and from the early days of the Web, I have advocated an emphasis on the site as an additional fundamental structuring unit. Because a single click can take the user to the other end of the world, every page needs to provide users with a sense of place and tell them where they have landed.

Explicit recognition of the site as a structuring mechanism is important for web usability, but most websites are much too large for the site level to provide the only structure. Much information can be hierarchically organized, and so an explicit representation of the hierarchy can be added to the top of the page to provide additional context and navigation options. For example, the intranet for the hypothetical BigCo company might have the following list of the nested hierarchy leading to the home page for the Stockholm office:

Each of the elements in the hierarchy list should be made a hyperlink to the appropriate top page for that level of the hierarchy. Note that the name of the lowest level of the hierarchy (here, Stockholm Office) should not be a link when displayed on the top page for that level. However, even the lowest-level name should be made active when displayed on a leaf page on that top level.

For information spaces that cannot easily be hierarchically structured, the subsite can be used as a helpful additional structuring mechanism. Subsites can also be used in hierarchical information spaces to give particular prominence to a certain level of the hierarchy, which is used as the subsite designator.

By subsite, I simply mean a collection of web pages within a larger site that have been given a common style and a shared navigation mechanism. This collection of pages can be a flat space, or it can have some internal structure, but in any case it should probably have a single page that can be designated the home page of the subsite. Each of the pages within the subsite should have a link pointing back to the subsite home page as well as a link to the home page for the entire site. Also, the subsite should have global navigation options (for example, to the site home page and to a site-wide search) in addition to its local navigation.

Subsites are a way of handling the complexity of large websites with thousands or even hundreds of thousands of pages. By giving a more local structure to a corner of the information space, a subsite can help users feel welcome in the part of a site that is of most importance to them. Also, a large site will often contain heterogeneous information that cannot all be squeezed into a single standard structure, so the capability to have subsites with somewhat different look-and-feel can provide an improved user experience. A subsite is a home environment for a specific class of users or a specific type of usage within a larger and more general site.

There is a tension between the desire of the subsite designer to optimize fully for the specific needs of local information versus the need for consistency across the entire site. Subsites should definitely not aspire to become independent sites with no relation to the parent site of which they are part and which should provide them with context and richness.

A good example of a subsite done right is ZDNet's AnchorDesk. AnchorDesk provides a platform for the respected computer industry commentator Jesse Berst to discuss current events in computing and pull together recommended links to additional information from across the rest of the Ziff-Davis site. The AnchorDesk subsite uses human editing as a guide to an otherwise overwhelming information space and has value-added use of hyperlinks to provide the foundation for the commentary.

Navigation Aids: Examples - Page 21
Designing Web Usability
Search Capabilities - Page 23