Created in 1946 as part of a 1,000 page Report on the Electronic Numerical Integrator and Computer (ENIAC), this ENIAC Operating Manual provides a fascinating glimpse into the technology behind the world's first electronic, general-purpose computer. Designed and built during WWII at the University of Pennsylvania, ENIAC was conceived by John Mauchly and J. Presper Eckert. It was financed by the Ordnance Department of the U.S. Army. The Army's intent was to use it to calculate artillery firing tables but ENIAC's digital, Turing-complete design meant that it could solve a wide range of...