A library catalogue is a systematic list of all the materials available in a library, including books, journals, and multimedia resources. It helps users find specific items by providing essential information such as titles, authors, publication dates, and locations within the library. Catalogues can be physical or digital, with many libraries now offering online access for convenience. Library catalogues often use a classification system, like the Dewey Decimal System or Library of Congress Classification, to organize materials by subject. Users can search catalogues using various criteria, such as keywords or categories, making it easier to locate desired resources efficiently.