Cardex is a term used to describe a system of organizing and storing information on index cards. These cards typically contain important details such as names, addresses, and contact information, making it easy to access and reference important data. The use of Cardex is commonly seen in businesses, libraries, and personal organization, providing a simple and efficient way to keep track of important information. The term can also refer to the physical storage unit or box that holds the index cards. With its straightforward design and versatility, Cardex remains a popular method for managing and organizing information.