The "First Draft of a Report on the EDVAC," by John von Neumann outlined the architecture of a stored-program computer. Previous methods had been clumsy; electronicly storing the programmed information and data was much more organized and advanced.

The leaders of building the ENIAC were John Mauchly and J. Presper Eckert. This computer was known for its speed, 5,000 operations per second. It took 3 years to build this computer. It took up 1,000 square feet of floor space. Input and output was controled by cards, lights, switches, and plugs.

Sir Frederick Williams of Manchester University modified a cathode-ray tube to display dots and dashes which represented binary ones and zeros. The IBM 701 and other vacuum tube computers used the Williams tube for memory.

William Shockley, Walter Brattain, and John Bardeen successfully tested this point-contact transistor.

Another early stored-program computer was the EDSAC, in 1949. This was made by Maurice Wilkes, at Cambrige University. The EDSAC could complete 714 operations per second.

The two year building project of the Manchester Mark I computer was lead by Frederick Williams and Tom Kilburn. This computer filled a medium - sized room. It composed of 1,300 vacuum tubes. Paper tape, switches and a teleprinter were the mediums of input and output.