Search in: Word
Vietnamese keyboard: Off
Virtual keyboard: Show
Computing (FOLDOC) dictionary
Electronic Numerical Integrator and Computer
Jump to user comments
computer (ENIAC) The second general-purpose electronic
digital computer and an ancestor of most computers in use
today. ENIAC was developed by Dr. John Mauchly and
J. Presper Eckert during World War II at the Moore School of
In 1940 Dr. John Vincent Atanasoff attended a lecture by
Mauchly and subsequently agreed to show him his computer, the
Atanasoff-Berry Computer (ABC), which was built between
1937-1942. Mauchly used ideas from the ABC in the design of
ENIAC, which was started in June 1943 and released publicly in
ENIAC was underwritten and its development overseen by
Lieutenant Herman Goldstine of the U.S. Army Ballistic
Research Laboratory (BRL). While the prime motivation for
constructing the machine was to automate the wartime
production of firing and bombing tables, the very first
program run on ENIAC was a highly classified computation
for Los Alamos. Later applications included weather
prediction, cosmic ray studies, wind tunnel design,
petroleum exploration, and optics.
ENIAC had 20 registers made entirely from vacuum tubes.
It had no other no memory as we currently understand it. The
machine performed an addition in 200 microseconds, a
multiplication in about three milliseconds, and a division
in about 30 milliseconds.
John von Neumann, a world-renowned mathematician serving on
the BRL Scientific Advisory Committee, soon joined the
developers of ENIAC and made some critical contributions.
While Mauchly, Eckert and the Penn team continued on the
technological problems, he, Goldstine, and others took up the
logical problems. In 1947, while working on the design for
the successor machine, EDVAC, von Neumann realized that
ENIAC's lack of a centralized control unit could be overcome
to obtain a rudimentary stored program computer.
Modifications were undertaken, that eventually led to an
instruction set of 92 "orders". Von Neumann also proposed
[R. F. Clippinger, "A Logical Coding System Applied to the
ENIAC", Ballistic Research Laboratory Report No. 673, Aberdeen
Proving Ground, MD, September 1948.