A library catalog is a systematic list of all the materials available in a library, including books, journals, magazines, and multimedia items. It helps users locate resources by providing essential information such as titles, authors, publication dates, and locations within the library. Most modern libraries use an online catalog, which allows patrons to search for items using keywords, categories, or specific criteria. This digital system often includes features like availability status and the ability to reserve items. The catalog is an essential tool for both library staff and users, enhancing the overall research experience.