Freebase is an open Creative Commons licensed graph database. It is not a database of graphs, but rather, 'graph' refers to the structure of the database. Instead of using tables and keys as in traditional databases, Freebase defines its data structure as a set of nodes and links between nodes. The concept of Freebase (previously known as MetaWeb) is helpfully explained in this video.

Freebase's data comes from a variety of sources and is freely available to view, use, download, edit and embed within your website. In addition, you can use Freebase to uniquely identify entities on the web, query Freebase's data, or build applications using Freebase's development platform. Freebase describes itself as a community of data-lovers. It allows you to 'follow' your favourite domains and users, and to communicate with other data-lovers.