A crucial aspect of most (if not all) Web systems is the way in which information is utilised and managed. Recent work on areas as diverse as topic maps, information architectures, adaptation of the Unified Modeling Language (UML), agile development methods such as extreme programming, and modelling for the semantic Web, have all contributed to an emerging understanding of how to design the information structures that underpin the Web (and of course much of this work has in turn been informed by research in areas like hypertext and HCI).
While current research has often produced effective models and processes, the research outcomes have had questionable impact on current commercial practice - something of significant concern as Web systems mature and become an increasingly integral element of our social infrastructure. Commercial development practices are typically either ad hoc or reflect the disciplinary background of the developers without adequately understanding the unique characteristics of Web systems – characteristics that have significant implications for the models that we might wish to construct and the approaches which should be taken to their development.
For example, a key characteristic of many Web systems (as well as various other software systems) is that the introduction of the system has a fundamental impact on the nature of the business processes and business models which are being supported by the system. In other words, the business environment and processes not only drive the definition of the system needs, but are in turn fundamentally changed by the system. This can be described as solutions and problems being mutually constituted – a concept well understood in the area of social informatics and requirements engineering. This in turn raises the issue of what models we might construct which help us understand how a system relates to (and affects) its business context.
Similar issues arise with various other of the unique characteristics of digital, online or Web systems. In effect, much work remains on supporting the wide adoption of emerging modelling approaches and development processes. There are numerous unanswered questions concerning aspects such as: what these models ought to capture; how they relate information design to functional design; and how the design process accommodates changing client and developer understanding of information designs during the development. This special issue provides a sample of work that is beginning to address some of these questions.
Calvo et al. look at how we might represent and manage content (particularly large repositories of information) through the use of machine learning and automatic document classification techniques. The result is a methodology that provides a solid step towards enabling the more effective management of information.
Kong et al. discuss a lightweight Web maintenance methodology which focuses on identifying the critical features in Web applications (so that these can be managed during the maintenance process). This provides an interesting perspective on what elements of Web systems are most crucial to understand and manage, and hence to ensure these are effectively modelled.
A design toolkit that supports a user-centered approach to development, and includes the use of ontologies to facilitate semantic support that allows for checking the consistency of modelling, is discussed by Montero et al. The toolkit also supports the automatic generation of project design documentation from the models.
Navarro et al. focus on the rapid prototyping of Web applications, and include modelling which distinguishes between content graphs and navigational schemas. The paper is particularly interesting given that it shows how a development process and modelling notation are inextricably intertwined.
Tongrungrojana and Lowe focus on WIED - a modelling notation that attempts to bridge the gap between business modelling and low-level information modelling by considering the flow of information within applications.
I hope you find this special issue a fascinating introduction to some of the key issues within the modelling of online and Web-enabled systems, and that it seeds some ideas about how this field might continue to evolve in the future.