Index card

Index cards are used for a wide range of applications and environments: in the home to record and store recipes, shopping lists, contact information and other organizational data; in business to record presentation notes, project research and notes, and contact information; in schools as flash cards or other visual aids; and in academic research to hold data such as bibliographical citations or notes in a card file.

Harrison's manuscript on the "ark of studies"[13] (Arca studiorum) describes a small cabinet that allows users to excerpt books and file their notes in a specific order by attaching pieces of paper to metal hooks labeled by subject headings.

[14] Harrison's system was edited and improved by Vincent Placcius in his well-known handbook on excerpting methods (De arte excerpendi, 1689).

[15] Carl Linnaeus, an 18th-century naturalist who formalized binomial nomenclature,[16] is said to have "invented the index card" c. 1760[1] in order to help deal with the information overload facing early scientists that occurred from overseas discoveries,[17] though there is room for dispute about whether he alone was the index card's inventor.

[1] In the late 1890s, edge-notched cards were invented, which allowed for easy sorting of data by means of a needle-like tool.

Similar catalogs were used by law firms and other entities to organize large quantities of stored documents.