Wikidata

Wikidata is a free and open knowledge base maintained by the Wikimedia Foundation. It provides a central repository for structured data that can be used by Wikimedia projects such as Wikipedia as well as external applications. Launched in 2012, Wikidata is built and maintained by a community of volunteers who edit and curate its content.

Data in Wikidata are organized into items (identified by Q numbers) and properties (identified by P numbers). A statement links an item to a value through a property and may include qualifiers and references to support the claim. Each item also stores labels, descriptions, and aliases in multiple languages, enabling multilingual data consumption. Wikidata uses the Wikibase software to support its data model and interfaces.

The data are released under CC0 1.0 Public Domain Dedication, allowing unrestricted reuse. Wikidata provides programmatic access through an API and a SPARQL-based query service (Wikidata Query Service), as well as downloadable data dumps for offline use.

Use and impact: its structured data underpin infoboxes and interlanguage links across Wikimedia projects, support advanced search, data journalism, and knowledge graphs, and are reused by developers and researchers outside Wikimedia. Governance is community-driven, with guidelines, references, and quality control administered by the Wikidata community under the Wikimedia Foundation.