W3C

RDFa Core Initial Context

This list of predefined prefixes have been defined for RDFa as an “initial context”: essentially, RDFa users can use these prefixes without having the obligation of defining the prefixes in the HTML code. The same list of prefixes have also been defined for JSON-LD as a JSON-LD Context at the URI http://www.w3.org/2013/json-ld-context/rdfa11; JSON-LD users can use the @context key with that URI as a shorthand to use the same prefixes.

Vocabulary Prefixes

Vocabulary Prefixes of W3C Documents (Recommendations or Notes)
Prefix URI Description For more details see Origin
as https://www.w3.org/ns/activitystreams# Activity Vocabulary Activity Vocabulary W3C Recommendation
csvw http://www.w3.org/ns/csvw# Metadata for Tabular Data Metadata Vocabulary for Tabular Data W3C Recommendation
dcat http://www.w3.org/ns/dcat# Data Catalog Vocabulary Data Catalog Vocabulary (DCAT) W3C Recommendation
dqv http://www.w3.org/ns/dqv# Data Quality Vocabulary Data on the Web Best Practices: Data Quality Vocabulary W3C WG Note
duv https://www.w3.org/ns/duv# Dataset Usage Vocabulary Dataset Usage Vocabulary W3C WG Note
grddl http://www.w3.org/2003/g/data-view# GRDDL Gleaning Resource Descriptions from Dialects of Languages (GRDDL) W3C Recommendation
jsonld http://www.w3.org/ns/json-ld# JSON-LD JSON-LD 1.1, A JSON-based Serialization for Linked Data W3C Recommendation
ldp http://www.w3.org/ns/ldp# Linked Data Platform Vocabulary Linked Data Platform 1.0 W3C Recommendation
ma http://www.w3.org/ns/ma-ont# Ontology for Media Resources Ontology for Media Resources 1.0 W3C Recommendation
oa http://www.w3.org/ns/oa# Web Annotation Vocabulary Web Annotation Vocabulary W3C Recommendation
odrl http://www.w3.org/ns/odrl/2/ ODRL Vocabulary & Expression 2.2 ODRL Vocabulary & Expression 2.2 W3C Recommendation
org http://www.w3.org/ns/org# Organizations The Organization Ontology W3C Recommendation
owl http://www.w3.org/2002/07/owl# OWL OWL Overview W3C Recommendation
prov http://www.w3.org/ns/prov# Provenance Vocabulary Provenance Ontology W3C Recommendation
qb http://purl.org/linked-data/cube# Data Cubes The RDF Data Cube Vocabulary W3C Recommendation
rdf http://www.w3.org/1999/02/22-rdf-syntax-ns# RDF RDF Semantics W3C Recommendation
rdfa http://www.w3.org/ns/rdfa# RDFa Vocabulary RDFa Core 1.1 W3C Recommendation
rdfs http://www.w3.org/2000/01/rdf-schema# RDF Schema RDF Semantics W3C Recommendation
rif http://www.w3.org/2007/rif# RIF RIF Overview W3C Recommendation
rr http://www.w3.org/ns/r2rml# R2RML R2RML: RDB to RDF Mapping Language W3C Recommendation
sd http://www.w3.org/ns/sparql-service-description# SPARQL 1.1 Service Description SPARQL 1.1 Service Description W3C Recommendation
skos http://www.w3.org/2004/02/skos/core# SKOS Core SKOS Simple Knowledge Organization System Reference W3C Recommendation
skosxl http://www.w3.org/2008/05/skos-xl# SKOS eXtension for Labels SKOS Simple Knowledge Organization System Reference W3C Recommendation
ssn http://www.w3.org/ns/ssn/ Semantic Sensor Network Ontology Semantic Sensor Network Ontology W3C Recommendation
sosa http://www.w3.org/ns/sosa/ Sensor, Observation, Sample, and Actuator Ontology Semantic Sensor Network Ontology W3C Recommendation
time http://www.w3.org/2006/time# Time Ontology Time Ontology in OWL W3C Recommendation
void http://rdfs.org/ns/void# VoID Describing Linked Datasets with the VoID Vocabulary W3C Interest Group Note
wdr http://www.w3.org/2007/05/powder# POWDER Protocol for Web Description Resources (POWDER): Formal Semantics W3C Recommendation
wdrs http://www.w3.org/2007/05/powder-s# POWDER-S Protocol for Web Description Resources (POWDER): Formal Semantics W3C Recommendation
xhv http://www.w3.org/1999/xhtml/vocab# RDFa Default Prefix RDFa Core 1.1 W3C Recommendation
xml http://www.w3.org/XML/1998/namespace XML Reserved Prefix Namespaces in XML 1.0 W3C Recommendation
xsd http://www.w3.org/2001/XMLSchema# XML Schema Datatypes XML Schema Part 2: Datatypes Second Edition W3C Recommendation

Some vocabularies are currently in development at W3C and they may become W3C Recommendations or Notes, i.e., may become part of the table above. It is therefore advisable to consider their prefixes reserved for now. These are:

earl
for “http://www.w3.org/ns/earl#”, see “Evaluation and Report Language (EARL) 1.0 Guide”
Widely used Vocabulary prefixes based on the vocabulary usage on the Semantic Web
Prefix URI Description For more details see
cc http://creativecommons.org/ns# ccREL ccREL: The Creative Commons Rights Expression Language
ctag http://commontag.org/ns# Common Tag Ontology Common Tag Specification
dc http://purl.org/dc/terms/ Dublin Core Metadata Terms DCMI Metadata Terms
dcterms http://purl.org/dc/terms/ Dublin Core Metadata Terms DCMI Metadata Terms
dc11 http://purl.org/dc/elements/1.1/ Dublin Core Metadata Element Set, Version 1.1 Dublin Core Metadata Element Set, Version 1.1
foaf http://xmlns.com/foaf/0.1/ FOAF FOAF Vocabulary Specification
gr http://purl.org/goodrelations/v1# GoodRelations Ontology GoodRelations Language Reference
ical http://www.w3.org/2002/12/cal/icaltzd# iCalendar terms in RDF iCalendar terms in RDF
og http://ogp.me/ns# Facebook's Open Graph protocol Open Graph Protocol
rev http://purl.org/stuff/rev# RDF Review Vocabulary RDF Review Vocabulary
sioc http://rdfs.org/sioc/ns# SIOC Core Ontology SIOC Core Ontology Specification
v http://rdf.data-vocabulary.org/# Google Rich Snippets' Vocabularies Rich snippets (microdata, microformats, and RDFa)
vcard http://www.w3.org/2006/vcard/ns# vCard in RDF Representing vCard Objects in RDF
schema http://schema.org/ The Schema.org vocabulary Full Schema.org documentation

Vocabulary Terms

Terms defined by W3C Documents
Term URI Description For more details see
describedby http://www.w3.org/2007/05/powder-s#describedby Refers to resource providing a description. POWDER: Formal Semantics, Section 5, POWDER Processor Semantics
license http://www.w3.org/1999/xhtml/vocab#license Refers to a license associated with this context. IANA Link Relations
role http://www.w3.org/1999/xhtml/vocab#role indicates the purpose of the resource. See the XHTML Role Vocabulary for roles in this vocabulary space XHTML Role Attribute Module
Ivan Herman, ivan@w3.org, W3C, Digital Publishing Activity Lead, Updated: 2020-05-09