About: http://webisa.webdatacommons.org/401112307

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	They allow a whole host of features including facebook, twitter, google login/commenting and some other cool stuff.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com