on-line public access computer

The term "on-line public access computer" (OPAC) refers to a library catalog that is accessible via computer. This system allows users to search for books and other materials in a library's collection. OPACs have evolved from earlier cataloging methods, such as book catalogs and card catalogs, by leveraging computer technology for faster and more comprehensive information retrieval.1

OPACs enable patrons to search for items using keywords, titles, or authors. They can also refine searches by combining multiple topics or ordering results by publication date. Modern OPACs often integrate additional library services, allowing users to reserve materials, check if items are currently on loan, and access information about journal articles or community resources. Cooperative cataloging efforts, like those facilitated by OCLC, have also contributed to the development and accessibility of these digital library resources.12