This is a picture of the ENIAC computer at the Moore School of Electrical Engineering of the University of Pennsylvania. It is available at Historic Computer Images.
History of Computing Information has a wealth of links to pictures and stories related to the development of the ENIAC and other computers.
The ENIAC was developed in the 1940's to compute firing and bombing tables for use by the U.S. in World War II.
From The ENIAC Story -
"By today's standards for electronic computers the ENIAC was a grotesque monster. Its thirty separate units, plus power supply and forced-air cooling, weighed over thirty tons. Its 19,000 vacuum tubes, 1,500 relays, and hundreds of thousands of resistors, capacitors, and inductors consumed almost 200 kilowatts of electrical power.
But ENIAC was the prototype from which most other modern computers evolved. It embodied almost all the components and concepts of today's high- speed, electronic digital computers. Its designers conceived what has now become standard circuitry such as the gate (logical "and" element), buffer (logical "or" element) and used a modified Eccles-Jordan flip-flop as a logical, high-speed storage-and-control device. The machine's counters and accumulators, with more sophisticated innovations, were made up of combinations of these basic elements.
ENIAC could discriminate the sign of a number, compare quantities for equality, add, subtract, multiply, divide, and extract square roots. ENIAC stored a maximum of twenty 10-digit decimal numbers. Its accumulators combined the functions of an adding machine and storage unit. No central memory unit existed, per se. Storage was localized within the functioning units of the computer."
Pretty amazing how much progress has been made in 60 years.
