# DCAT — Data Catalog Vocabulary
## Overview
DCAT is the W3C standard for describing datasets and data catalogues in RDF (Resource Description Framework), enabling federated data discovery across distributed repositories. Published as a W3C Recommendation (DCAT v1: 2014, DCAT v2: 2020, DCAT v3: 2024), it is the vocabulary that makes data catalogues interoperable: a dataset described with DCAT in [[Recherche Data Gouv]] can be harvested and found through the [[EOSC]] portal, [[data.gouv.fr]], and other DCAT-compliant catalogues without any manual re-entry.
## Core Classes
| Class | Description |
|---|---|
| `dcat:Dataset` | A logical collection of data (e.g. a neuroimaging cohort) |
| `dcat:Distribution` | A specific form/download of a dataset (e.g. a ZIP file, an API endpoint) |
| `dcat:Catalog` | A curated collection of dataset metadata (e.g. Recherche Data Gouv catalogue) |
| `dcat:DataService` | An API or endpoint providing access to data |
## DCAT-AP
DCAT-AP is the European Application Profile of DCAT — a specification that adds requirements and recommendations specific to European public sector data. It is the standard for data portals in the EU Open Data Portal and for EOSC.
## Connections
- Extends: [[Dublin Core]] (builds on DC terms)
- Required by: [[EOSC]] (DCAT-AP for cross-portal discovery)
## Resources
- https://www.w3.org/TR/vocab-dcat/ (W3C DCAT specification)
- https://joinup.ec.europa.eu/collection/semantic-interoperability-community-semic/solution/dcat-application-profile-data-portals-europe (DCAT-AP)