A library catalog is a listing of all the items held by a particular library. When the item is entered into the library's online catalog database, information is entered into different fields, which are then searchable by users. You can't find a reference to a particular poem in the library catalog, nor to a particular essay within a book of essays. The same is true of magazines, journals and newspapers. The library catalog will tell you if the library keeps a particular periodical in its collection, but will not list all the articles within the periodical, nor will it necessarily even list all the issues of the periodical which are kept.
Most catalogs are searchable by author, title, subject and keyword.
Some of the important things you need to know about the information in those fields is discussed below. An excellent tutorial for using a typical academic library catalog system can be found at the University of Wisconsin-Parkside Library. The entire series of Parkside's tutorial units and another outstanding tutorial from the Houston Community College System are linked at Library Tutorials . Searching the catalog by subject and keyword The subject field of a catalog record contains only the words or phrases used by the cataloguer when assigning a subject heading. Unless you type in that entire phrase as your search term, you won't find the book by searching the subject field.