1913-

American mathematician involved in the development of the Electronic Numerical Integrator and Computer (ENIAC), the first electronic digital computer. Designed for the U.S. Army, this first prototype contained 18,000 vacuum tubes and was used to compute ballistic tables. After leaving the Army in 1945, he joined the Institute for Advanced Study. There, with John von Neumann, he helped build the prototype of the present-day computer using a magnetic drum for data storage.