- Data value: the result that comes out of a reference. E.g. using the JSONPath reference formulation returns JSON data values.
- Data value type: the datatype of a data value. For certain sources (e.g. JSON), this datatype is returned as part of the data value, for other sources (e.g. SQL), this datatype can be requested via the SQL protocol.
- The natural RDF datatype: corresponding to a data value type, natural RDF datatypes can be specified.
Unless otherwise specified, the natural RDF datatype is a [[plain literal]] without [[language tag]].