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Hypertext is the computer storage of information as fragmented but linked multi‐dimensional documents. Such systems offer many advantages over the printed word, for example for group authorship of documents or to allow more creative access to the data, although there are some drawbacks. The design of chunky and creamy hypertext systems, the way in which information is presented to the end user and the relevant merits of the technique are discussed.

Examines the concept of hypertext and how it relates to the World Wide Web, along with a discussion of why this is important to librarians. Includes examples of library Web pages and products that take advantage of the medium and some that do not, along with a specific discussion of crafting text, structure and linking for the Web.

Hypertext may transform the practice and culture of science by opening up texts for comment and verification in ways which have previously been impossible. A brief introduction is given to the technology of hypertext, and the effects are explored in contexts which range from the conceptual base of science (modelling, and how and why this is done) to laboratory techniques. Some critical areas of impact are then identified. By allowing us to see, for example, what lies behind protocols and official versions, hypertext may reduce the incidence of scientific fraud; it can stimulate creativity by amplifying the frame of reference and revealing new facts to researchers; it can challenge the exercise of authority by offering access to original or unorthodox material which may be rejected in the process of peer review; it can provide an inside track in a discipline for novices or outsiders who reconstruct the readings of experienced practitioners. Existing systems may be applied to some of the purposes which are described, though the costs of unsubsidised investment may inhibit development.

Interchange of text and hypertext between various systems is vital in order to reuse text and hypertext, but the task of generating translators between different representations is often complex and tedious. The Integrated Chameleon Architecture (ICA) is a public domain toolset for generating translators. However, ica can only handle context‐free grammars while the grammar of hypertext is not context‐free. This paper presents an extended ICA (E‐ICA) which is based on ICA with extra pre‐ and post‐processors to handle the context‐sensitive and implicit information of hypertext. A system called SGML‐MUCH has been developed using E‐ICA. The development and use of the SGML‐MUCH system is presented as a case study with converters for the hypertext systems MUCH, Guide, Hyperties, and Toolbook described in detail.

In a hypertext database, the information is presented as a network of nodes connected by links. Such nodes may be text, graphics, audio, video, and even other software. Although hypertext provides a new approach to information management, it also leaves a whole new set of problems for the designers of the hypertext database to solve. As the volume of information grows, the task of authoring a hypertext database becomes much more complex. In this article, the author presents the experiences during the development of a hypertext version of the user's guide for information services on JANET, in the UK, by using HyperPAD, a hypertext shell for the IBM PC. It may be the first step to explore the proper way to solve those problems which come together with the increasing application of hypertext.

This paper aims to review the literature on the utility of employing the construct of cognitive style in understanding behaviour in web‐based learning environments.

The paper initially examines whether the web architecture may be matched to an individual's cognitive style in order to facilitate learning, before progressing to assess whether different architectures influence a web users' internal representations of web‐based learning systems, as measured by concept map drawings. Other issues explored are users' web navigation and users' sense of learning community when receiving instruction via web‐based learning environments.

The studies reviewed indicate that cognitive style is a pertinent factor for consideration when assessing the success with which users engage with web‐based learning systems.

Some of the studies reviewed here are small‐scale and caution is urged in generalising the findings.

In terms of the practical implications, however, it is suggested that web‐based systems should be designed with consideration to individual differences in user characteristics, as this is related to the success with which users learn, navigate and interact socially in an online environment. However, it is concluded that more research is required in order to produce general rules relating cognitive style to the use of web‐based learning systems.

The findings from the numerous studies on the implications of considering the function of individual differences in using web‐based learning are notable and useful in the context of web‐based instruction.

An important stage in the process of retrieval of objects from a hypertext database is the creation of a set of inter‐nodal links that are intended to represent the relationships existing between objects; this operation is often undertaken manually, just as index terms are often manually assigned to documents in a conventional retrieval system. Studies of conventional systems have suggested that a degree of consistency in the terms assigned to documents by indexers is positively associated with retrieval effectiveness. It is thus of interest to investigate the consistency of assignment of links in separate hypertext versions of the same full‐text document, since a measure of agreement may be related to the subsequent utility of the resulting hypertext databases. The calculation of values indicating the degree of similarity between objects is a technique that has been widely used in the fields of textual and chemical information retrieval; in this paper, we describe the application of arithmetic coefficients and topological indices to the measurement of the degree of similarity between the sets of inter‐nodal links in hypertext databases. We publish the results of a study in which several different sets of links are inserted, by different people, between the paragraphs of each of a number of full‐text documents. Our results show little similarity between the sets of links identified by different people; this finding is comparable with those of studies of inter‐indexer consistency, where it has been found that there is generally only a low level of agreement between the sets of index terms assigned to a document by different indexers.

Ubiquitous web applications (UWA) are a new type of web applications which are accessed in various contexts, i.e. through different devices, by users with various interests, at anytime from anyplace around the globe. For such full‐fledged, complex software systems, a methodologically sound engineering approach in terms of model‐driven engineering (MDE) is crucial. Several modeling approaches have already been proposed that capture the ubiquitous nature of web applications, each of them having different origins, pursuing different goals and providing a pantheon of concepts. This paper aims to give an in‐depth comparison of seven modeling approaches supporting the development of UWAs.

This methodology is conducted by applying a detailed set of evaluation criteria and by demonstrating its applicability on basis of an exemplary tourism web application. In particular, five commonly found ubiquitous scenarios are investigated, thus providing initial insight into the modeling concepts of each approach as well as to facilitate their comparability.

The results gained indicate that many modeling approaches lack a proper MDE foundation in terms of meta‐models and tool support. The proposed modeling mechanisms for ubiquity are often limited, since they neither cover all relevant context factors in an explicit, self‐contained, and extensible way, nor allow for a wide spectrum of extensible adaptation operations. The provided modeling concepts frequently do not allow dealing with all different parts of a web application in terms of its content, hypertext, and presentation levels as well as their structural and behavioral features. Finally, current modeling approaches do not reflect the crosscutting nature of ubiquity but rather intermingle context and adaptation issues with the core parts of a web application, thus hampering maintainability and extensibility.

Different from other surveys in the area of modeling web applications, this paper specifically considers modeling concepts for their ubiquitous nature, together with an investigation of available support for MDD in a comprehensive way, using a well‐defined as well as fine‐grained catalogue of more than 30 evaluation criteria.

HIFI (ESPRIT Project 6532) creates a set of tools to allow a reader to access a large body of heterogeneous information, managed by external databases created beforehand, through a hypertext interface. Information currently found in information systems is based on different media and is usually managed by different tools, like relational databases and a variety of multimedia database systems. Sometimes the need arises to ‘browse’ through the information using an interactive and intuitive interface. Hypertext is probably the best current means for interactive (and possibly intuitive) navigation through a heterogeneous body of information. Available hypertext tools, however, are usually seen as being for managing their own information rather than being an interface for accessing external databases. The HIFI approach is based on a model‐based description of the hypertext application, as it appears to the reader. A declarative and/or operational mapping translates hypertext operations (search, queries and navigation) into operations on the underlying information base and also ‘materialises’ hypertext objects, using objects of the underlying databases. The system also implements methodologies to support the hypertext interface development process. Real‐life applications will be developed to show the validity of the approach, with the cooperation of important end‐users who will cooperate with the project directly, either as partners or sponsors.