MarkLogic includes tools to index and store semantic graphs in the form of RDF triples. You can search and manage those triples using native SPARQL query and SPARQL Update, and do inference to discover new facts about your data. MarkLogic can function as a document store for triples embedded in documents and as a triple store for triples in graphs. These semantic capabilities can be accessed natively or through JavaScript, XQuery, and REST.
Each RDF triple represents a fact (John Smith lives in London) in the form of a statement made up of a subject, predicate, and object. Groups of triples are stored as RDF graphs. Here is a model of a simple RDF graph that contains three triples:
Using this graph, we could ask who lives in England? and learn that both John Smith and Jane Smith live in England.
To get started with Semantics, see Introduction to Semantic Graphs in MarkLogic and Getting Started with Semantic Graphs in MarkLogic in the Semantic Graph Developer's Guide.