Although cognitive psychology showed much initial promise, it has failed to make significant contributions to the study of human-computer interaction, which has led to a rejection of cognitivism in favour of situated action theory. The authors accept that the critique has much to offer, but reject the outright abandoning of cognitivism. Cognitive psychology needs a common language in which to describe interaction between people and artifacts: two examples of research in progress are described, one focused on events, the other on representations and the relationship between the information display and the conceptual model. Cognitive psychology also needs a better delivery method than the traditional research paper, and the idea is proposed of a vocabulary of ‘cognitive dimensions’, terms which can be meaningfully used by non-specialists (who will recognise familiar but uncrystallised concepts) and which can be used as indexes to the professional literature. These two components form a proposal for improving the effectiveness of cognitive psychology. The paper ends with the hope that mainstream cognitive psychology will broaden its area of enquiry.

This article reviews the extensive literature emerging from studies concerned with skill acquisition and the development of knowledge representation in programming. In particular, it focuses upon theories of program comprehension that suggest programming knowledge can be described in terms of stereotypical knowledge structures that can in some way capture programming expertise independently of the programming language used and in isolation from a programmer's specific training experience. An attempt is made to demonstrate why existing views are inappropriate. On the one hand, programs are represented in terms of a variety of formal notations ranging from the quasi‐mathematical to the near textual. It is argued that different languages may lead to different forms of knowledge representation, perhaps emphasizing certain structures at the expense of others or facilitating particular strategies. On the other hand, programmers are typically taught problem‐solving techniques that suggest a strict approach to problem decomposition. Hence, it seems likely that another factor that may mediate the development of knowledge representation, and that has not received significant attention elsewhere, is related to the training experience that programmers typically encounter. In this article, recent empirical studies that have addressed these issues are reviewed, and the implications of these studies for theories of skill acquisition and for knowledge representation are discussed. In conclusion, a more extensive account of knowledge representation in programming is presented that emphasizes training effects and the role played by specific language features in the development of knowledge representation within the programming domain.

Software engineers have developed sophisticated “object‐oriented” programming environments that are intended to make the reuse of program code easy. Experience has shown that these environments can be improved: Even very experienced programmers have problems in locating and comprehending code for reuse. Programs cannot be modified as readily as had been anticipated. We describe the problems in terms of “cognitive dimensions” of notational systems and show how improved support for opportunistic design may be achieved. A central tenet is that programmers are not at present able to externalize enough of their knowledge about a program. We propose a scheme for attaching a “description level” in which arbitrary attributes and relationships can be recorded in a “browsable” form. Our conclusions stress improving the means for programmers to represent facts rather than the provision of predefined knowledge bases.