The ENIAC

ENIAC (Electronic Numerical Integrator And Computer) was the first large-scale, electronic, digital computer. In 1943 The US Ballistics Research Laboratory commissioned the engineers John Mauchly and John Presper Eckert of the University of Pennsylvania to build a computer to produce tables of ballistics data, such as the trajectories of artillery shells. The result, completed in 1946, was ENIAC. The ENIAC used 18000 valves, 70,000 resistors, 10,000 capacitors (which stored electrical charge), 600 switches, 20,000 vacuum tubes and 40 racks of equipment. It was 30 m (100ft) long, weighed some 30 tonnes and performed 5000 additions a second and ran up a daily electric bill of $60, a large amount at the time, the mid 1940s.