Library card

Library card for the National Central Library in Taiwan

A library card can refer to several cards traditionally used for the management of books and patrons in a library. In its most common use, a library card serves similar functions as a corporate membership card. A person who holds a library card has borrowing or other privileges associated with the issuing library. The library card also serves as a method of identification. When a person chooses an item to borrow and presents their library card to the library, they take responsibility for the borrowed item and promise to abide by certain rules, usually including a promise to return the item by the due date or face a library fine. If the cardholder violates these responsibilities, their borrowing privileges may be suspended.

An example of a borrowing card, formerly in common use to track books