Designing user interfaces is a challenging job. Interfaces to aid the navigation of document spaces have been the subject of an increasing number of research studies. This paper addresses the concept of “document spaces” and “navigation.” Various interface designs are explored. The movement toward integrated interface designs for navigation at multiple levels of a document space is also explored.
The amount of electronic information is increasing dramatically. The ubiquity of computers coupled with the development of networks is facilitating the generation and distribution of information. The number of Web pages already exceeds 800 million (Lawrence & Giles, 1999), and is growing at an exponential rate (Myers, 1993). Some have suggested that ultimately a Web page may be only read once -- by its owner -- because that the rate of the World Wide Web growth exceeds the user-reading rate. It is increasingly difficult to find information in this massive information space.
Researchers are looking at tools to manage the various information spaces. This paper focuses on one subset of tools, navigation tools, as one method of finding information. Further, the focus is on one type of information space -- a document space. There are not many papers which explicitly define a document space. As a result, studies of the effectiveness of various tools may be confusing, if in reality these tools are operating on very different kinds of document spaces. A document space has many special properties and attributes. A careful review of what is meant by a document space and a classification of the various subspaces will give some hints for design of suitable navigation tools. Examples of existing systems related to a document space will be presented. The notion of what constitutes a document space will be discussed.
From the very first library at Alexandria to the electronic repositories on the Web, it has been clear that browsing is one method people like to use to find information. The space, place, and movement metaphor is easy to understand. The knowledge of location and place can be easily obtained by most users with little conscious attention. For this reason, navigation is one of the activities that is likely to take place in any document space. The design of improved navigational tools will contribute to the overall efficiency and effectiveness of applications. The navigation concept will be investigated in detail by exploring the concept of navigation in the physical world and comparing that to the concept of navigation in a document space. Both the functionality and information provided by various types of navigation tools will be addressed.
The document space and the navigation process meet at the user interface. There are many ways to present and interact with the interface. Presentation and interaction techniques are explored in order to speculate on the scope of the navigation tool design space.
There are already many kinds of navigation tools. In order to improve their effectiveness, integration among tools is proposed as a key factor. The idea comes from Spring, Morse, and Heo (1996) who discussed a set of interrelated tools that play a role in different phases of navigation. Many empirical studies show that an addition navigation tool increases effectiveness in navigation (Nielsen, 1989;Wright & Lickorish, 1990). How navigation tools might be integrated will be investigated.
Preliminary Definition of Terms
Many terms used in information science literature have multiple meanings. The terms, as used in this paper, are defined below. The definitions for some terms will be expanded in later sections. Preliminary definitions are given as follows:
Document: an artifact in some symbolic form which is generated to convey communication.
Document Space: a collection of documents which have some common attributes.
Navigation: a process of moving in space including mental perspective.
Navigation tools: tools that help us in navigation. These include tools to navigate and tools that give information for navigation.
Application: a collection of tools to support some general job.
Tool: a specific software tool with a user interface for one specific task.
User Interface: a presentation and a set of interactions under the control of software that can be perceived and known by users.
Presentation: a mapping of internal data in the system to output devices of the computer system. The presentation includes visual display and sound. In this paper, it will be addressed in terms of the visual perspective only.
Interaction: the action between user and software. The action may or may not be acknowledged by software. For example, a user may look at a screen and this would be an interaction but there would be no input to the software system.