Abstract: As semantic web and linked data became hot topics, new standards in metadata, including bibliographic vocabularies and ontologies, were published in RDF or OWL. IFLA’s ISBD Vocabularies and FRBR Vocabularies, RDA Registry, Europeana Data Model (EMD) Vocabulary, OCLC’s BiblioGraph (bibliographic extension of Schema.org), and Library of Congress’s BIBFRAME are emerging in recent years. There is discrepancy in amount of classes and properties between these RDF vocabularies. The tendency in the making of RDF vocabularies is coordinating among agencies, minimizing number of namespaces, and introducing “event” class into the vocabularies.

Key words: RDF vocabularies, Bibliographic metadata, Metadata standard