Index cards stacked

Stacked index cards in a studio still life, evoking cataloging systems and study methods.

About this subject

Index cards, also known as flashcards or note cards, are paper-based tools for organizing information dating back to the 18th century. Carl Linnaeus, the Swedish naturalist, used a card system for classifying species, a precursor to modern catalogs. In the 19th century, libraries adopted them as the standard for book catalogs, with standardized sizes (usually 3x5 inches). In Brazil, they were widely used in public and school libraries until digitization. In education, index cards became popular for active recall studying, especially for languages and exams. In agile software development, index cards are used to write user stories, promoting simplicity and focus. Even today, despite digital tools, many people prefer the tactile feel and lack of distractions of physical cards for intensive study, such as preparing for the Enem or certification exams.

Frequently Asked Questions

What is the standard size of an index card?

The most common size is 3x5 inches (7.6x12.7 cm), but other sizes like 4x6 inches and 5x8 inches also exist.

How are index cards used in agile methodologies?

In agile, index cards represent user stories, tasks, or bugs. They are handwritten, making them easy to move and rearrange on a kanban board.

Are paper index cards still relevant in the digital age?

Yes, many students and professionals prefer them for their simplicity, tactile feedback, and lack of distractions, especially for techniques like spaced repetition.