This year marks the 80th anniversary of ENIAC, the first general-purpose digital computer. The computer was built during World War 2 to speed up ballistics calculations, but its contributions to computing extend well beyond military applications. Two of ENIAC’s key architects—John W. Mauchly, its co-inventor, and Kathleen “Kay” McNulty, one of the six original programmers—married a few years after its completion and raised seven children together. Mauchly and McNulty’s grandchild Naomi Most deli...