A library catalog is a database of the materials held by a library. This can include books, periodicals, digital resources, and other types of materials. A library catalog is used to help users find the materials they are looking for, and it typically includes information such as the title, author, publication date, and a brief description of the material. Users can search the library catalog by keyword, title, author, or subject to find specific materials. Many libraries also have an online catalog that can be accessed remotely, allowing users to search for materials and place holds on items from anywhere with an internet connection.