Help Users Manage Large Amounts of Information - Page 20

Web navigation is a challenge because of the need to manage billions of information objects. Right now, the Web "only" has about a billion pages, but around 2005, there will be 10 billion pages online that can be reached from any Internet-connected device. Current user interfaces are simply not well suited to deal with such huge amounts of information. Virtually every current user interface is more or less a clone of the Macintosh user interface from 1984 (which again was a close copy of research at Xerox PARC in the late 1970s and early 1980s). The Mac was optimized to handle the few documents that an individual user would create and store on his or her disk. Even the PARC research was mostly aimed at office automation where the main goal was to support a workgroup and a few thousand documents. The Web, in contrast, is a shared information environment for millions of users (soon to be hundreds of millions of users) with incredibly many more documents.

Web browsers are applications in the style of the currently dominant UI paradigm, so they are inherently ill suited for the task of browsing the Web. Consider, for example, how a pull-down menu (even with pull-right submenus) is an extraordinarily weak way of organizing a user's bookmarks. Calling the menu "favorites" instead of "bookmarks" does not change its fundamental limitations.

Current software is extremely weak at addressing the Web's navigation problems, meaning that the designers of web content have to help solve the problem. Actually, the problems in navigating an information space as large as the Web are probably so hard to solve that we will need all the help we can get, both from better software and from better-designed content.

The Web's early days were dominated by simplistic hypertext links: Everybody pointed to everybody else in a very unstructured manner. In fact, it was quite common to have very long lists of recommended links without much in the way of explaining why the links would be of interest to a user. The assumption was that the Web was so interesting and the users so curious, that they would check out all the links and be grateful the more links they got.

Long hotlists have certainly become less prevalent. Now, there is a renewed appreciation of the value of selective linking, where links have added value because they have been carefully chosen by an author to be the best or most relevant to that author's audience.

Sitemaps are becoming somewhat of a cliche. All users say they want sitemaps, and we even know from hypertext research that overview diagrams help users find information faster, so I am not opposed to sitemaps. But current sitemaps do not seem to help users much. For example, they lack the one feature that any mall- goer knows to be essential for a map: the "you are here" indicator. Many sites seem to design their sitemaps as a simple list of all their stuff. A better solution would be a dynamic sitemap that indicates the page from which it was accessed and that has ways of highlighting information of interest to specific user populations.

Future Navigation

We need to stop thinking of navigation as being the responsibility of either the browser or the server in isolation. Instead, it needs to become a shared responsibility of the client, the server, and shared resources such as proxy servers. So, for example, I would expect the server to send a sitemap definition in XML to the client so that the browser can integrate it with maps of other regions of the Web frequented by the user and then generate a customized navigation map for that individual user. This map could then be annotated with quality ratings downloaded from a proxy server that kept track of what pages and/or sites the user's colleagues had found useful in the past. You could imagine a map of places to go that had been color-coded according to how many other users had found each area useful.

Reducing Navigational Clutter

We obviously cannot represent every single information object in a navigation UI (given that there are so many). Instead, designs must employ a variety of methods to reduce the clutter. Some useful methods are:

• Aggregation (showing a single unit that represents a collection of smaller ones). This can be done quite easily within a site (indeed, the very notion of a "site" is one useful level of aggregation, as are various levels of subsites), but it may be harder to aggregate across sites.
• Summarization (ways of representing a large amount of data by a smaller amount). Examples include the use of smaller images to represent larger ones and the use of abstracts to represent full documents. We need ways of summarizing large collections of information objects.
• Filtering (eliminating entire wads of stuff we don't care about). Collaborative filtering and quality-based filters are particularly useful (for example, only show stuff that other people have found to be valuable).
• Truncation. Cut off everything except the first initial parts of the information and let users click a "More..." link for the rest.
• Example-based representations. Instead of showing everything, show some representative examples and say something like "3 million more objects."
  The User Controls Navigation - Page 19
  Designing Web Usability
  Navigation Aids: Examples - Page 21