1943 — May 17th: Development Starts on ENIAC
The US Army contracted The University of Pennsylvania to construct the vacuum tube mainframe for calculating ballistic firing data. ENIAC was designed by J. Presper Eckert and John William Mauchly in the Moore School of Engineering. ENIAC was online from Feb 14, 1946 to Nov 9, 1946 when it was moved to the Aberdeen Proving Grounds in Maryland and received upgrades. It was turned back on July 29th, 1947 and ran continuously until 1955.