DataTerminology.comNEW
An RDF property asserting that a resource is an instance of a class.
DESCRIPTION
rdf:type links a resource to its class, forming the basis for typing in RDF. It enables inference, validation, and query patterns that rely on class membership. Turtle provides a compact keyword ‘a’ as shorthand for rdf:type. Tools and reasoners use rdf:type to manage instance classification and derive memberships via subclass hierarchies. It is central in ontologies, SKOS, and domain models.
ALTERNATIVE DEFINITIONS
W3C RDF Schema 1.1
The type property may be used to state that a resource is an instance of a class.
Directly describes rdf:type’s purpose in membership assertions.
W3C Turtle
The keyword a is a shorthand for rdf:type.
Shows practical, compact syntax for rdf:type in Turtle.
Apache Jena
rdf:type asserts that a resource is an instance of a class, enabling classification and reasoning over class hierarchies.
Highlights reasoning implications in developer practice.
RELATED TERMS
RDF Schema rdfs:Class RDF Turtle SPARQL OWL SHACL Knowledge Representation Class Hierarchy Simple Knowledge Organization System
COMPETING TERMS
a
KNOWLEDGE AREAS
Semantic & Knowledge Modeling Data Modeling
TARGET AUDIENCE
Data Modeler Data Engineer Software Developer AI Engineer Data Architect
EXTERNAL SOURCES
- Wikipedia - Resource Description Framework
- W3C - Canonical definition of rdf:type
- W3C - Turtle shorthand for rdf:type
- W3C - SPARQL querying of class membership
TOP QUESTIONS
What does rdf:type do?
It asserts that a resource is an instance of a given class, forming the foundation of typing in RDF.
Category: Definition
How do I use rdf:type in Turtle?
Use the keyword ‘a’ as shorthand; example: ex:Alice a ex:Person.
Category: Syntax
Why is rdf:type important for reasoning?
Reasoners infer memberships through subclass hierarchies when rdf:type assertions exist.
Category: Importance
What is a common mistake with rdf:type?
Confusing properties with classes when asserting types; ensure the object is a class.
Category: Mistakes
How to query rdf:type in SPARQL?
Use triple patterns like ?s a ex:Class or ?s rdf:type ex:Class to match instances.
Category: Practice
Can a resource have multiple rdf:type values?
Yes, an individual may belong to multiple classes reflecting multiple roles or categories.
Category: Clarification
What’s the relation between rdf:type and SHACL?
SHACL shapes can validate properties and constraints for instances of specific classes.
Category: Integration
Does rdf:type exist in JSON-LD?
JSON-LD uses @type to express type information equivalent to rdf:type.
Category: Integration
How do tools handle rdf:type?
Libraries and stores index types for efficient queries and reasoning over class hierarchies.
Category: Tooling