(last updated 2012-09-12) Resource Identifier (RI) Scheme name: callto Status: provisional Scheme syntax: callto: or callto: Scheme semantics: Launching Skype call (+And in Hungary the KLIP Software call too) (unofficial; see also skype:) Encoding considerations: Unknown, use with care. Applications/protocols that use this scheme name: Introduced with Microsoft NetMeeting. Works with current version of Skype with Internet Explorer, Opera and Safari Interoperability considerations: Unknown, use with care. Security considerations: Unknown, use with care. Contact: Registering party: Alexey Melnikov Scheme creator: Microsoft Author/Change controller: Either the registering party or someone who is verified to represent the scheme creator. See previous answer. References: http://daringfireball.net/2005/12/callto_uris_safari, http://tools.ietf.org/html/draft-antti-telephony-url-00 (file created 2012-09-12)