Built by physicist John Mauchly and engineer John Presper Eckert, Jr., at the Moore school of engineering at the University of Pennsylvania, the ENIAC (Electronic Numerical Integrator and Computer) was the first fully functional digital computer. In use from February 1946 until October 1955, ENIAC was initially built for the U.S. military to calculate the paths of artillery shells. It was later used for calculations in nuclear weapons research, weather prediction and aerodynamics.
ENIAC filled an entire room, weighed thirty tons, and consumed two hundred kilowatts of power. It was comprised of over 19,000 vacuum tubes along with fifteen hundred relays and hundreds of thousands of resistors, capacitors and inductors. The electronics filled forty-two panels nine feet tall, two feet wide and one foot thick. Input and output were via punch cards.
The patent for the ENIAC was assigned to Sperry Rand Corporation, which sued Honeywell Corporation for patent infringement. In the ensuing battle over rights to the fundamental technology of electronic digital computing, the court invalidated the Mauchly/Eckert patent in light of earlier work done by physicist John V. Atanasoff at Iowa State College.
Notwithstanding the court decision, there is no doubt that modern computing owes a great debt to Mauchlyís and Eckertís revolutionary invention.