An ecology of knowledge: technical and institutional developments in computing, 1900-1945 -- Biography and the circulation of knowledge: John Mauchly and the origins of electronic computing -- From ecology to network: John von Neumann and postwar negotiations over computer-development research -- Knowledge and organization: redefining computer-development research at the national bureau of standards -- Research and rhetoric: Jay Forrester and federal sponsorship of academic research -- Institutions and border crossings: Cuthbert Hurd and his applied science field men -- Voluntarism and occupational identity: the IBM users' group, share -- Research and education: the academic computing centers at MIT and the University of Michigan -- Discipline and service: research on computer time sharing at MIT and the University of Michigan.