Data federation

A form of scalable, virtual integration in which the actual data remain where they are, rather than being moved from their sources.

Linked Data

A means of exposing, sharing, and connecting individual data elements with the help of fixed addresses or global identifiers called Uniform Resource Identifiers (URIs).

Resource Description Framework (RDF)

A World Wide Web Consortium (W3C) data model that allows relationships between data elements to be described in graph form, a form that makes large-scale federation of disparate data sources possible.

Semantic Protocol and RDF Query Language (SPARQL)

The W3C’s recommended standard for querying Web data in RDF graphs. In an RDF-based environment, graphical tools with SPARQL engines can join and query hundreds of sources through a point-and-click interface.

Semantic Web

An evolution of the World Wide Web in which data descriptions are explicit, making it possible to federate, query, browse, and gather information from disparate internal and external sources. The result is more complete and relevant information.


A description of the characteristics of data elements and the relationships among them within domains. Ontologies describe relationships in an n-dimensional manner, illuminating relationships of multiple kinds among elements, whereas taxonomies show just hierarchical relationships.