The collaborative production of computer commands in command and control

The division of labour, in its turn, implies interaction; for it consists not in the sheer difference of one man's kind of work from that another, but in the fact that the different tasks and accomplishments are parts of a whole to whose product all, in some degree, contribute. And wholes, in the human social realm as in the rest of the biological and in the physical realm, have their essence in interaction. Work as social interaction is the central theme of sociological and social psychological study of work.Hughes (1958)In an interaction with a computer the user receives information that is output by the computer, and responds by providing input to the computer ? the user's output becomes the computer's input and vice versa.Dix, Finlay, Abowd and Beale (1993, p. 11)In this paper, we examine the details of the use of a computer system in situ. Drawing from recent developments in the social sciences, we adopt an analytic orientation that is distinctive from much current work in human?computer interaction and cognitive engineering. Rather than focusing on a circumscribed activity of an individual at a computer system, we explore how the production of computer-based activities is sensitive to the ongoing work and interaction of the participants in the setting. The study utilizes materials including fieldwork and audio-visual recordings to explore how one particular technology is used, a system for automatically controlling trains on an urban transportation system. We focus on the “uses” of this system, a fairly conventional command-and-control system, in the Control Room, and examine how the technology is immersed within the action and interaction of the participants. In particular, we explore how the entry of commands into the system by one controller is coordinated with the conduct of colleagues, and how their conduct is inextricably embedded in their colleague's use of the system. It also reveals how the activities of controllers are managed from moment to moment, so that a division of labour emerges through the course of their interaction. Although in drawing upon naturalistic materials, this study contributes to the growing corpus of “workplace studies” within the field of computer-supported cooperative work, by examining the details of computer-based activities it continues the tradition within human-computer interaction of being concerned with the detailed use of technologies. Indeed, the emerging distinction between the two fields, one considered as focusing on matters associated with the individual “user”, and the other on the “group”, may be false.