Conceptualizing a possible discipline of human–computer interaction John M. Carroll Center for Human–Computer Interaction and College of Information Sciences and Technology, The Pennsylvania State University, University Park, PA 16802, USA article info Article history: Received 19 May 2009 Received in revised form 7 November 2009 Accepted 20 November 2009 Available online 27 November 2009 Keywords: Theory Disciplinary model Science Engineering Craft abstract This essay is a personal reflection on John Long’s keynote address at the BCS People and Computers meet- ing in Nottingham in the summer of 1989. I try to locate the paper’s purpose and significance within the history of human-computer interaction (HCI), both prior to 1989 and subsequently, and particularly with respect to the abiding questions of what sort of enterprise HCI is, and of what sorts of knowledge it uses and produces. Ó 2009 Elsevier B.V. All rights reserved. 1. Introduction: HCI’s first three decades Human–computer interaction (HCI) is an area of research and practice that emerged in the early 1980s, initially as a specialty area in computer science. HCI has expanded rapidly and steadily for three decades, attracting professionals from many other disci- plines and incorporating diverse concepts and approaches. To a considerable extent, HCI now aggregates a collection of semi-dis- tinct fields of research and practice in human-centered informatics. However, the continuing synthesis of disparate conceptions and approaches to science and practice in HCI has produced a dramatic example of how different epistemologies and paradigms can be reconciled and integrated. Until the late 1970s, the only humans who interacted with com- puters were information technology professionals and dedicated hobbyists. This changed disruptively with the emergence of per- sonal computing around 1980. Personal computing, including both personal software (productivity applications, such as text editors and spreadsheets, and interactive computer games) and personal computer platforms (operating systems, programming languages, and hardware), made everyone in the developed world a potential computer user, and vividly highlighted the deficiencies of comput- ers with respect to usability for those who wanted to use comput- ers as tools. The challenge of personal computing became manifest at an opportune time. The broad project of cognitive science, which incorporated cognitive psychology, artificial intelligence, linguis- tics, cognitive anthropology, and the philosophy of mind, had formed at the end of the 1970s. Part of the programme of cognitive science was to articulate systematic and scientifically-informed applications to be known as ‘‘cognitive engineering”. Thus, at just the point when personal computing presented the practical need for HCI, cognitive science presented people, concepts, skills, and a vision for addressing such needs. HCI was one of the first examples of cognitive engineering. Other historically fortuitous developments contributed to the establishment of HCI. Software engineering, mired in unmanage- able software complexity in the 1970s, was starting to focus on nonfunctional requirements, including usability and maintainabil- ity, and on non-linear software development processes that relied heavily on testing. Computer graphics and information retrieval had emerged in the 1970s, and rapidly came to recognize that interactive systems were the key to progressing beyond early achievements. All these threads of development in computer sci- ence pointed to the same conclusion: The way forward for comput- ing entailed understanding and better empowering users. Finally human factors engineering, which had developed many techniques for empirical analysis of human–system interactions in so-called control domains such as aviation and manufacturing, came to see HCI as a valuable and challenging domain in which hu- man operators regularly exerted greater problem-solving discre- tion. These forces of need and opportunity converged around 1980, focusing a huge burst of human energy, and creating a highly visible interdisciplinary project. One of the most significant achievements of HCI is its evolving model of the integration of science and practice. Initially this mod- 0953-5438/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.intcom.2009.11.008 E-mail address: jmcarroll@psu.edu Interacting with Computers 22 (2010) 3–12 Contents lists available at ScienceDirect Interacting with Computers journal homepage: www.elsevier.com/locate/intcom