What does a 650 tag indicate in a MARC record?

A 650 tag in a MARC (Machine-Readable Cataloging) record indicates a topical subject heading. This tag is used to provide a controlled vocabulary term or phrase that describes the subject content of a bibliographic item. By using subject headings, librarians can help users find materials relevant to specific topics or themes more efficiently, as these headings are standardized to ensure consistency and improve searchability within library catalogs.

In cataloging practices, the use of subject headings is crucial because it allows for better organization of materials and aids users in locating resources. Typically, the 650 tag is followed by the specific subject heading that matches the content of the material being cataloged, allowing for effective subject indexing.

The other options—author name, date of publication, and material type—are represented by different tags in MARC records. The author’s name is typically indicated by the 100 or 110 tags, the date of publication is found within the 260 or 264 tags, and material type is represented by other tags such as 008 or 300. Understanding these differences helps librarians and catalogers accurately create and interpret MARC records.