freebase

Freebase was a large, collaborative knowledge base that stored structured information about people, places, organizations, and other topics. It organized data as topics connected by a graph of relationships and attributes. Each topic had a unique machine identifier (MID) and could be assigned multiple types (for example, /people/person or /location/location) and a set of claims that described properties or links to other topics or literals.

Data model and access methods: Freebase used a graph-based data model built around topics, types, and claims. Queries could be written in the Metaweb Query Language (MQL) to retrieve complex structures, and a public RESTful API allowed applications to search, read, and integrate Freebase data. The platform also offered data dumps for offline use, enabling developers and researchers to work with the knowledge graph outside the live service.

History and provenance: Freebase was developed by Metaweb Technologies and publicly launched in 2007. In 2010, Google acquired Metaweb and began integrating Freebase data into its broader knowledge efforts. The project contributed to the growth of structured data on the web and influenced how search engines present fact-based information.

Shutdown and legacy: Google announced deprecation of Freebase in the mid-2010s, and the Freebase API and website were shut down in 2016. Data exports were provided to facilitate migration and reuse, and some Freebase content contributed to Google's knowledge graph and other open-data initiatives. Freebase is often cited as a precursor to modern large-scale knowledge graphs and as an example of community-curated structured data on the web.