bibliotekkatalogen

A bibliotekkatalogen is a structured database that libraries use to describe, locate, and access resources in their collections. It covers physical and digital materials, including books, periodicals, maps, audio-visual items, and electronic resources. Each catalog entry provides bibliographic data (title, author, edition, publisher, year), access points (authors, subjects), identifiers (ISBN, ISSN, OCLC number), and holdings information (library branch, call number, shelf location, item status).

Catalogs are driven by metadata standards and cataloging rules. Traditional catalogs used MARC 21 records and AACR2; modern workflows commonly employ RDA for bibliographic data and MARC or MARC 21 for machine-readable records. More recently, FRBR-based models and the BIBFRAME framework support linking records, works, expressions, and agents, while authority control and subject headings (LCSH, Norwegian equivalents) improve search accuracy. Many libraries adopt linked data and consolidate records via discovery layers.

Types and interfaces: national catalogs combining multiple libraries into a union catalog; OPACs (online public access catalogs) that provide user-facing search; discovery layers that index library catalogs along with digital repositories. Users can search by title, author, subject, ISBN, or keyword, and refine results with filters such as format, language, or year. Holdings data informs availability and location; persistent identifiers enable linking to digital copies.

Evolution: from card catalogs to online catalogs and federated search; increasing emphasis on digital materials, linkable data, and interlibrary loans. The bibliotekkatalogen remains a central tool for collection management, resource discovery, and user access in libraries.