The recent evolution of western societies has been characterized by an increasing emphasis on information and communication. As the amount of available information increases, however, the user -- worker, student, citizen -- faces a new problem: selecting and accessing relevant information. More than ever it is crucial to find efficient ways for users to interact with information systems in a way that prevents them from being overwhelmed or simply missing their targets. As a result, hypertext systems have been developed as a means of facilitating the interactions between readers and text. In hypertext, information is organized as a network in which nodes are text chunks (e.g., lists of items, paragraphs, pages) and links are relationships between the nodes (e.g., semantic associations, expansions, definitions, examples -- virtually any kind of relation that can be imagined between two text passages). Unfortunately, the many ways in which these hypertext interfaces can be designed has caused a complexity that extends far beyond the processing abilities of regular users. Therefore, it has become widely recognized that a more rational approach based on a thorough analysis of information users' needs, capacities, capabilities, and skills is needed. This volume seeks to meet that need.
From a user-centered perspective -- between systems and users -- this volume presents theoretical and empirical research on the cognitive processes involved in using hypertext. In so doing, it illustrates three main approaches to the design of hypertext systems: