A tool which identifies or directs you to a source of information. The Online Catalog is a major access tool in the Colorado State University Libraries. It gives you call number and location information for books and journals. A directional reference work such as a guide to the literature or INDEX which provides CITATIONS to books or journals is also an access tool.

a computerized database or print source that helps you find the book, article, document, audiovisual or other material that you need

A tool that provides systematic access to the contents of information, for example, indexes, catalogs and bibliographies.