Ontologies provide rich semantics as well as the structured relationships needed to interpret data. As interoperability between information, metadata and standards becomes more important, it will become increasingly relevant that digital curators have a means of understanding the wide range of information associated with digital objects. Ontologies are created by a community of people who want to provide tools for describing and querying resources within a particular domain. This might include metadata schemas and classification systems, and are useful to specify concepts of information within a domain of interest. Interoperability between various ontologies will also become increasingly important in enabling members of disparate communities to re-use and understand digital information over time.