when was the first computer built
1 1946 - ENIAC-World's first electronic, large scale, general-purpose computer, built by Mauchly and Eckert, and activated at the University of Pennsylvania in 1946. 2  ENIAC recreated on a modern computer chip.3  See an explanation of ENIAC on a Chip by the Moore School of Electrical Engineering, University of Pennsylvania. 1976 - CRAY 1 - The world's first electronic digital computer, developed in 1946. 2  A 75MHz, 64-bit machine with a peak speed of 160 megaflops, (one million floating point operations per second) the world's fastest processor at that time.