Methods&Tools p27-39

I Introduction In recent years, specialists in human–computer interaction (HCI) have come to appreciate the importance of understanding the context in which computer-supported activities take place [1]. Such understanding directly affects design and evaluation by revealing what users are up to and how they might most effectively use a technology. The idea is to gain this understanding before the design process has progressed too far, or during evaluation, when openings for modifications and improvements to the technology exist. There have been several attempts to come up with tools and techniques to support taking context into account in the design and evaluation of computer technologies. These approaches include task analysis [6], participa-tory design [3], and contextual design [7], among others. However, contextual factors are notoriously elusive and difficult to pin down [5], so there is still a need for conceptual tools to deal with context at a practical level. The existing approaches to context are for the most part " bottom up " ones. They start with an empirical analysis of contextual factors and gradually develop concepts such as " task decomposition " [6], " future workshops " [3], or " flow models " [7], which later can be put in an appropriate theoretical framework. From our point of view, this " bottom up " or empirically-driven strategy can be complemented with a " top down " one, that is, starting with an abstract theoretical representation of context and then situating this representation in the reality of design and evaluation. Borrowing Brown and Duguid's well-known metaphor [5], we can say that if it is difficult to grapple with the " whale " of context by trying to get a firm grip on its specific parts, let's try a large net instead. In this paper we present a tool that is directly shaped by a general theoretical approach—activity theory [10, 11, 18]. Activity theory provides a broad theoretical framework for describing the structure, development , and context of human activity. In the 1990s, activity theory has been applied to problems of human–computer interaction by an international community of scholars and practitioners [1–4, 8, 9, 12]. Activity theory is framed by several basic principles (explained in the next section): hierarchical structure of activity, object-ori-entedness, internalization and–externaliza-tion, tool mediation, and development. These general principles help orient thought and research, but they are somewhat abstract when it comes to the actual business of working on …