"An index card (or record card in British English and system cards in Australian English) consists of card stock (heavy paper) cut to a standard size, ...
[Read more]
used for recording and storing small amounts of discrete data. A collection of such cards either serves as, or aids the creation of, an index for expedited lookup of information (such as a library catalog or a back-of-the-book index). This system was invented by Carl Linnaeus, around 1760." - (en.wikipedia.org 05.01.2021)
