Search results
Results from the WOW.Com Content Network
A notched card showing two levels of notching. Edge-notched cards or edge-punched cards are a system used to store a small amount of binary or logical data on paper index cards, encoded via the presence or absence of notches in the edges of the cards. [1]
A single program deck, with individual subroutines marked. The markings show the effects of editing, as cards are replaced or reordered. Many early programming languages, including FORTRAN, COBOL and the various IBM assembler languages, used only the first 72 columns of a card – a tradition that traces back to the IBM 711 card reader used on the IBM 704/709/7090/7094 series (especially the ...
When use of the ticket punch proved tiring and error-prone, Hollerith developed the pantograph "keyboard punch". It featured an enlarged diagram of the card, indicating the positions of the holes to be punched. A printed reading board could be placed under a card that was to be read manually. [35]: 43 Hollerith envisioned a number of card sizes.
Cards were sorted on one card column at a time; sorting on, for example, a five digit zip code required that the card deck be processed five times. Sorting an input card deck into ascending sequence on a multiple column field, such as an employee number, was done by a radix sort , bucket sort , or a combination of the two methods.
Aperture cards are used for engineering drawings from all engineering disciplines. The U.S. Department of Defense once made extensive use of aperture cards, and some are still in use, but most data is now digital. [2] Information about the drawing, for example the drawing number, could be both punched and printed on the remainder of the card.
A punched card sorter is a machine for sorting decks of punched cards. Sorting was a major activity in most facilities that processed data on punched cards using unit record equipment. The work flow of many processes required decks of cards to be put into some specific order as determined by the data punched in the cards.
This category contains articles about punched cards and card handling equipment, including card readers, card punches, and keypunches. Subcategories This category has the following 2 subcategories, out of 2 total.
Cards are read and punched one column at a time and binary cards are permitted. Cards are read using photocells, [8] illuminated by fiber optics, unlike the IBM 1402, which uses wire brushes to read cards. It is even possible to create (but not read, except in Binary Mode [9]) "IBM Doilies," cards with every possible hole punched. Few other ...