Resource Description Framework

tags

Semantic Web

W3C standard data model. Originally intended for metadata, now typically used for interchange of graph data. Basic structure is the subject/object/predicate triple.

Cool things I do with RDF. | Dean Allemang

RDF is just an abstract model. There are many serialization formats:

• RDF/XML (probably what someone means if they say they have an "RDF file")
  
• JSON-LD
  
• Turtle: Compact and human-readable. Probably the most popular today
  
• N-Triples: Similar to Turtle, but line-based so simpler to parse
  
• Notation3: Superset of Turtle. Adds some features beyond plain RDF, like inference rules. Basis for AIR via N3Logic. Non-standard. Don't confuse with N-Triples
  

Some significant extensions:

• RDF Schema (RDFS): Set of RDF classes for description of ontologies
  
• RDF-star (formerly RDF*): Adds quoted triples for conceptually sound reification. That is, you can use a triple as the subject of another triple and add e.g. provenance information. Note that basic RDF does have some facilities for reification but they suck. Maybe RDF-star doesn't really solve the fundamental problem that it's hard to know what to reify¹
  

Some RDF tools I've heard good things about