WebFinger

Enables WebFinger (RFC 7033) support for WordPress.

About WebFinger:

WebFinger is used to discover information about people or other entities on the Internet that are identified by a URI using standard Hypertext Transfer Protocol (HTTP) methods over a secure transport. A WebFinger resource returns a JavaScript Object Notation (JSON) object describing the entity that is queried. The JSON object is referred to as the JSON Resource Descriptor (JRD).

(quote from the RFC)