Triplestores are a form of database used to store semantic web data.. RDF is encoded as subject--predicate--object triples and the triplestore stores and indexes these triples in order to make them easy to query and process. Often SPARQL is used to query a triplestore. The quadstore is an extension of the triplestore to store multiple graphs, that is collections of triples with a common origin or use.
Defined on page 395
Used on pages 395, 396, 397, 417