Freebase: a shared database of structured general human knowledge
Kurt Bollacker, Robert L. Cook, Patrick Tufts · 2007
Freebase is a practical, scalable, graph-shaped database of structured general human knowledge, inspired by Se-mantic Web research and collaborative data communi-ties such as the Wikipedia. Freebase allows public read and write access through an HTTP-based graph-query API for research, the creation and maintenance of struc-tured data, and application building. Access is free and all data in Freebase has a very open (e.g. Creative Com-mons, GFDL) license.