Historical Computer Engineering - Punchcard
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Punchcard

History

Punch cards have already been used in the beginning of the 18th century. Their existens has been justified by being able to repeatedly do tasks over and over again while just discribing them once. Early on those cards were used for weaving looms and until today they can be found in barrel organs. Their design varied from time to time, as well as the material (wood, paper, card; etc.).
The origin of the punch cards are old music boxes with cylinders with little pins on it. The break through of punched cards came due to their efficiency compared to cylinders or related technologies. Codes and programs could be reproduced quickly.

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In 1833 the first tabulator machines have been controlled by punch cards. In 1890 this technology assisted the census in the USA. Therefor the German-American Herman Hollerith invented a machine that reduced the time for the evaluation from seven years to only four weeks. After that the punched cards have been implemented for other evaluations as well, especially when it came to handle much data.

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In 1928 a standard format has been established, that suggested dimensions about the size of a one Dollar note. Three years later, in 1931, IBM introduced the multiplier IBM 600, a machine that was externaly programmed with a panel.

1941 the Z3 of Konrad Zuse that used punched tape code has been finished, the first electrical computer. The MARK-I build by Howard Aiken in 1949 was controlled by punched tape as well. At IBM the switchpanel programing was replace by punch card systems in 1949. In the 1980's punch card systems have been driven out of the market by magnetical and optical memory technologies. Even though IBM states that punch cards do have some adventages over modern mass storage devices:

  1. Those storage devives are not only to be read by machines but manualy as well.
  2. The signal-energy ratio does not exceet a value of ten.

By now IBM reinstated punch cards because with modern techniques they are able to store more data on those mechanical storage than on magnetical devices. One terabit of data fits on one square inch of a punch card. Thereby the information units have a spatial extent in the range of nanometers. An adventage to the original paper punch cards: the new cards from synthetic materials are rewritable. This technology is not even completely exhausted.