Google Talk is also the name of the client applications offered by Google to access the service. Google Talk applications are available for Microsoft Windows (XP, Server 2003, Vista, and Windows 7), Android, Blackberry, and Google Chrome OS operating systems.
Because the Google Talk servers communicate with clients using an open protocol, XMPP, the service can also be accessed using any other client that supports XMPP. Such clients are available for a number of operating systems not supported by the Google Talk client.
VoIP in Google Talk uses an older version of what became the Jingle protocol. The technology used within the Google server network, however, is not publicly known.
