EDSAC, the first full-size stored-program computer, built at the University of Cambridge, Eng., by Maurice Wilkes and others to provide a formal computing service for users. EDSAC was built according to the von Neumann machine principles enunciated by the Hungarian American scientist John von Neumann and, like the Manchester Mark I, became operational in 1949. Wilkes built the machine chiefly to study computer programming issues, which he realized would become as important as the hardware details.