DCMI Abstract Model
The DCMI Abstract Model ("DCAM"), developed between 2003 and 2007 and now considered superseded by newer models, described the design of metadata records in terms of structural components, such as Descriptions, Statements, Properties, and (literal or non-literal) Values, in order to enable structural validation of RDF-based metadata.
DCAM was intended to bridge the gap between RDF, a better-known though still controversial abstract model optimized for integrating metadata interoperably, and older, mainstream mainstream metadata technologies such as databases and XML. The enduring contribution of DCAM was to treat graph-based metadata in terms of bounded and fixed Description Sets (or records) subject to structural validation. Such validation can be achieved today with Shape Expressions Language (ShEx) and Shapes Constraint Language (SHACL).