Index cards stacked

Stacked index cards: discover the history and uses of these classic office items that revolutionized information organization.

About this subject

Index cards, also known as catalog cards or file cards, are small rectangular pieces of cardboard used to record information in a standardized way. Popularized in the 19th century with the expansion of libraries and archives, they allowed efficient cataloging of books, documents, and data. American inventor Melvil Dewey, creator of the Dewey Decimal System, was among the first to adopt the standardized size of 3 x 5 inches (7.5 x 12.5 cm), which became the international standard.

In office environments, index cards were the backbone of filing systems such as card files. Companies, hospitals, and governments used these cards to keep records of clients, patients, inventories, and references. Each card had a header and fields filled by hand or typewriter, organized in specific drawers or boxes. The technique of note-taking, with concise annotations and cross-references, was taught in administration and library science courses.

With digitization, physical use of index cards declined, but they are still employed in creative and educational contexts. Artists and designers use them for brainstorming, storyboarding, and rapid prototyping. Moreover, the organizational principle of cards inspired note-taking management software like Notion and Trello, which virtually replicate the logic of cards. Interestingly, the term “flashcard” for memorization directly derives from these cards.

In Brazil, index cards were widely used in public and school libraries until the 2000s. The wooden card catalog with metal drawers was a common piece of furniture in government offices. Even today, individual cards can be found in stationery stores, sold in packs with specific rulings or lines for each purpose. The simplicity and effectiveness of this physical system ensure its lasting place in the history of information organization.

Frequently Asked Questions

What is the standard size of an index card?

The international standard size is 3 x 5 inches (7.5 x 12.5 cm), popularized by Melvil Dewey in the 19th century. Other common sizes include 4 x 6 inches and 5 x 8 inches.

Are index cards still used today?

Yes, although their use has declined with digitization, they are still employed in creative, educational, and physical filing systems in some libraries and offices.

What is the relationship between index cards and software like Trello?

Software like Trello and Notion uses the concept of cards to organize tasks and information, directly inspired by the physical index card system.