ENIAC 1946
The ENIAC (Electronic Numerical Integrator and Computer) project was based at the University of Pennsylvania in the 1940s. ENIAC was the first large-scale computer, developed in 1946 by John Mauchly and J. Presper Eckert with the help of Hermann Goldstine. Goldstine’s wife, Adele, assisted in its creation. It was used by the military for various tasks, one of which was doing calculations for the design of a hydrogen bomb. ENIAC used vacuum tubes instead of electromechanical relays, which were usual in other computing devices at the time. The vacuum tubes were the equivalent to transistors in a modern microprocessor – they could switch their state to either the on or off position.

Kay Mauchly was one of the first computer programmers on ENIAC, and is John Mauchly's widow. She recollects her experience of the project.