ENIAC

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Detail of the back of a section of ENIAC, showing vacuum tubes

ENIAC (which meant "Electronic Numerical Integrator And Computer")[1] was a computer built in 1943. It was designed by two people called John Mauchly and J. Presper Eckert. The machine was built out of nearly 17,500 vacuum tubes,[2] 7,200 diodes and many miles of wire.[3] It took up 1,800 square feet (170 m2) of space, which is the size of a large room.[4]

Because the computer was built out of vacuum tubes, it often broke. This meant that someone had to find the broken tube (which was not an easy job), take the broken tube out and put a working tube in.

Making programs for the computer was hard. Making the computer ready for one single program could take many days or even weeks. This was because the programming had to be done by pulling wires from one place to another. This was not hard for small programs, but if a large program was wanted, it was very hard work. Programming by pulling wires was used until 1948, when a special type of memory (called Read Only Memory (ROM), because it could only be read from by the computer) was added. After that, programming was done by using switches, meaning that the time to make a program was reduced (made smaller) to hours instead of days.

The ENIAC was first designed to print firing tables for the U.S Navy, but the war had finished before the machine was completed.

When it was asked if it was possible to make a hydrogen bomb, ENIAC gave the answer in 20 seconds. ENIAC took 70 hours to work out pi to 2000 decimal places. A modern PC with a CPU of the size of 2x2 cm is much faster than ENIAC, which used up a whole room of space. For an example, a modern PC can work out a million (1 000 000) decimal places of pi in about ten seconds.

ENIAC was shut down forever on October 2, 1955.[1] Now, only about 10 panels of the 40 exist.

Sources[change | edit source]

  1. 1.0 1.1 Weik, Martin H. (January-February 1961). "The ENIAC Story". O R D N A N C E. Ftp.arl.mil. http://ftp.arl.mil/~mike/comphist/eniac-story.html. Retrieved 2010-10-06.
  2. St. Clair Kilby, Jack (17 September, 2001). "Turning Potential into Realities: The Invention of the Integrated Circuit" (pdf). ChemPhysChem. Wiley Online Library. p. 483. http://onlinelibrary.wiley.com/doi/10.1002/1439-7641(20010917)2:8/9%3C482::AID-CPHC482%3E3.0.CO;2-Y/pdf. Retrieved 2010-10-05.
  3. Weik, Martin H. (December 1955). "Ballistic Research Laboratories Report № 971 — A Survey of Domestic Electronic Digital Computing Systems — page 41". US Department of Commerce. http://ed-thelen.org/comp-hist/BRL-e-h.html. Retrieved 2010-10-05.
  4. Weik, Martin H. (December 1955). "Ballistic Research Laboratories Report № 971 — A Survey of Domestic Electronic Digital Computing Systems — page 41". US Department of Commerce. http://ed-thelen.org/comp-hist/BRL-e-h.html. Retrieved 2009-04-16.