Edge-notched card
Index card with notches to store data
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. The notches allow efficient sorting of a large number of cards in a paper-based database, as well as the selection of specific cards matching multiple desired criteria.
Unlike machine-readable punched cards, edge-notched cards were designed to be manually sorted by human operators. They are also informally called needle cards since they can be sorted with the help of long knitting needles. In the mid-20th century they were sold under names such as Cope-Chat cards, E-Z Sort cards, McBee Keysort cards, and Indecks cards.
History
An early instance of a methodology similar to edge-notched cards appeared in 1904. Edge-notched cards were used for specialized data storage and cataloging through much of the 20th century. They were gradually replaced by computer storage.
Formats
Cards existed in many variants, with differing sizes and numbers of rows of holes. The center of the card could be blank for information to be written onto, or contain a pre-printed form.
Begin with the source’s own compact description: “Edge-notched card” is index card with notches to store data. The dossier treats that line as a proposition to test through Edge-notched, card and Index, not as a finished interpretation.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Mar 13, 2026. The linked authority identifier is Q5337636. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1904.
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This entry incorporates text from “Edge-notched card” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.