Inspired by Hill and Hollan's original work [6], we have been developing a theory of interaction history and building tools to apply this theory to navigation in a complex information space. We have built a series of tools --- map, trails, annotations and signposts --- based on a physical-world navigation metaphor. These tools have been in use for over a year. Our user study involved a controlled browse task and showed that users were able to get the same amount of work done with significantly less effort. Keywords information navigation, information foraging, interaction history, Web browsing INTRODUCTION Digital information has no history. It comes to us devoid of the patina that forms on physical objects as they are used. In the non-digital world we make extensive use of these traces to guide our actions, to make choices, and to find things of importance or interest. We call this area interaction history; that is, the records of the interactions of people and objects. Physical o...

rom the beginning, hypermedia application design has been driven primarily by technological innovations and constrained by technical feasibility. For the last few years, however, usability methods and results from human factors research have been gaining more influence [17]. Despite this trend toward user-oriented development procedures, issues of cognition and human information processing still are widely neglected and barely influence hypermedia design.

While developing the software of a browser-operated educational CD-ROM, we had to face a number of problems. This paper presents these problems and the solutions we found. Amusingly, most of our solutions rely on continuations. Are browsers and multimedia the future of continuations?

Hypertext systems are being used in many applications because of their flexible structure and the great browsing freedom they give to diverse communities of users. However, this same freedom and flexibility is the cause of one of its main problem: the "lost in hyperspace" problem. One reason for the complexity of hypertext databases is the large number of nodes and links that compose them. To simplify this structure we propose that nodes and links be clustered forming more abstract structures. An abstraction is the concealment of all but relevant properties from an object or concept. One type of abstraction is called an aggregate. An aggregate is a set of distinct concepts that taken together form a more abstract concept. For example, two legs, a trunk, two arms and a head can be aggregate together in a single higher level object called a "body." In this paper we will study the hypertext structure, i.e., the way nodes are linked to each other in order to find aggregates in hypertext da...

Most hypermedia systems emphasize the integration of graphics, images, video, and audio into a traditional hypertext framework. The hyperspeech system described in this paper, a speech-only hypermedia application, explores issues of navigation and system architecture in an audio environment without a visual display. The system under development uses speech recognition to maneuver in a database of digitally recorded speech segments; synthetic speech is used for control information and user feedback. In this research prototype, recorded audio interviews were segmented by topic, and hypertext-style links were added to connect logically related comments and ideas. The software architecture is data driven, with all knowledge embedded in the links and nodes, allowing the software that traverses through the network to be straightforward and concise. Several user interfaces were prototyped, emphasizing different styles of speech interaction and feedback between the user and machine. In additio...

Research on understanding linear texts has shown that comprehension and navigation mainly depend on the reader's ability to construct a coherent mental representation. While the author of a traditional document can use a variety of structural cues to support his readers in building up such a representation, the author of a hyperdocument faces a new problem. If he wants to ensure that his readers understand the entire hyperdocument as a coherent entity, he needs means to indicate its structure in a comprehensible way. In this paper, we propose a construction kit which provides dedicated design objects for this purpose. The design objects can be characterized as building blocks for three functionally different components of a hyperdocument: its content part, organizational part, and presentation part. In addition to the design objects, we propose some design rules which should guide the construction of coherent hyperdocuments. Keywords Design of hyperdocuments, coherent hyperdocuments,...

HyperCafe is an experimental hypermedia prototype, developed as an illustration of a general hypervideo system. This program places the user in a virtual cafe, composed primarily of digital video clips of actors involved in fictional conversations in the cafe; HyperCafe allows the user to follow different conversations, and offers dynamic opportunities of interaction via temporal, spatio-temporal and textual links to present alternative narratives. Textual elements are also present in the form of explanatory text, contradictory subtitles, and intruding narratives. Based on our work with HyperCafe, we discuss the components and a framework for hypervideo structures, along with the underlying aesthetic considerations. KEYWORDS: Aesthetics, multi-threaded narratives, navigation, temporal links, digital video. A VISIT TO HYPERCAFE You enter the Cafe, and the voices surround you. Pick a table, make a choice, follow the voices. You're over their shoulders looking in, listening to what t...

Early hypertext systems were monolithic and closed, but newer systems tend to be open, distributed, and support collaboration. While this development has resulted in increased openness and flexibility, integrating or adapting various different tools, such as content editors, viewers or even other link servers has remained a tedious task. Many developers were implementing essentially similar components, simply for the benefit of having their own platform on which to experiment with hypertexts. The open hypermedia community is addressing this issue of interoperability between open hypermedia systems. The goal of the community is to provide an open hypermedia framework that can be used by application developers outside the community to construct more powerful hypermedia-aware applications. The design and evolution of this framework is presented along with the requirements that drove its development. The framework has matured to the point where it has supported the creation of a number of research prototypes. These prototypes are described and evaluated with respect to their use of the framework.

This paper introduces the notion of context-aware mobile hypermedia. Contextawareness means to take the users' context such as location, time, objective, community relations etc. into account when browsing, searching, annotating, and linking. Attributes constituting the context of the user may be sensed automatically and/or be provided by the user directly. When being mobile the user may achieve context-aware hypermedia support on a variety of small and medium sized computing platforms such as mobile phones, PDAs, tablet PCs and laptops.

This paper presents the experience gained in developing and using the hypertext functions of the Grif system. Grif is a structured document editor based on the generic structure concept: each document is represented in the system by its logical structure which is an instance of a generic structure. This notion of logical structure encompasses both hierarchical structures (as is usual in structured documents) and non-hierarchical links (as is usual in hypertext). The document model on which Grif is based is presented, focusing on the different types of links. Various applications using these links are also described. It is shown that the approaches of electronic documents and hypertext, which are often opposed to each other, can be combined for building more powerful integrated systems.