Screenshot of Google Talk
|Stable release||(December 13th, 2007) [+/−]|
|Preview release||Google Talk, Labs Edition [+/−]|
|Operating system||Windows 2000,
Windows Server 2003,
|Available in||English, German, French, Italian, Japanese, Korean, Dutch, Polish, Portuguese, Russian, Turkish, Chinese, Spanish|
|Type||VoIP/Instant messaging client|
|Website||Google Talk Labs Edition Google Talk gadget|
Google Talk (GTalk) is a free Windows web-based application for instant messaging and voice over internet protocol (VOIP), offered by Google Inc. The first beta version of the program was released on August 24, 2005.
Instant messaging between the Google Talk servers and its clients uses an open protocol, XMPP, allowing users of other XMPP/Jabber clients to communicate with Google Talk users. VoIP in Google Talk uses an older version of what would later become the Jingle protocol. The technology used within the Google server network however is not publicly known.
The Google Talk client is only available for Microsoft Windows (2000, XP, Server 2003, Vista and Windows 7), but Google Chat (voice and video chat) is now available for PCs and Intel-based Macs. Google Talk mobile clients are also available for the Palm Pre, BlackBerry, iPhone and Android-based devices. With the release of the Google Talk gadget, users of all platforms supported by Adobe Flash Player can also use Google Talk. Many other XMPP clients are compatible with Google Talk, and support a variety of other platforms.
Google has announced that a major goal of the Google Talk service is interoperability. Google Talk uses XMPP to provide real-time extensible messaging and presence events, including offline messaging and voice mailing. On January 17, 2006, Google enabled server-to-server communications, federating itself with any XMPP server that supports the dialback protocol.
On February 7, 2005, Gmail received chat functionality, using Ajax for server–browser communication, and was integrated with Google Talk. Users can send instant messages to other Gmail users. As it works within a browser, Google Talk does not need to be downloaded to send instant messages to Gmail users.
Conversation logs are automatically saved to a Chats area in the user's Gmail account. This allows users to search their chat logs and have them centrally stored in their Gmail accounts. It does not, however, appear possible to download chat logs that are not attached to an e-mail conversation. 
Since November 8, 2006, Google has also integrated Google Talk with Orkut. This enables Google Talk users to interact with registered Orkut users, by sending and receiving 'scraps' within Orkut.
It is also possible to display the song currently playing on one's computer.
Also, as of November 11, 2008, the new Google Chat supports voice and video chat between Gmail users and Google Talk users - on some systems, not all major OSs are supported. The Gmail user requires a plugin download and installation, but is otherwise seamlessly integrated into the Gmail interface. As of September 2009, the plugin is only available for Windows (XP and Vista) and Mac OS X (only on Intel-based Macs).
The connection between the Google Talk client and the Google Talk server is encrypted, except when using the international version of the client, Gmail's chat over HTTP, a federated network that doesn't support encryption, or when using a proxy like IMLogic. Thus messages are not necessarily encrypted end-to-end, although it is possible to have end-to-end encryption over the GTalk network using OTR (off-the-record) chat when all participants connect over HTTPS. Some XMPP clients also natively support encryption with Google Talk's servers.
On July 28, 2006, Google added voicemail and file sending capabilities to the Google Talk client. Voicemail messages can be 10 minutes long, and they're delivered to the contact's mailbox as an attached MP3 file (11 kHz mono 24kbit/s). Recipients who use Gmail are offered better integration. Gmail recognizes that it is a voicemail message, and users can choose to stream the file using the integrated MP3-playing applet, or to download the MP3 file.
On October 31, 2006, Google introduced offline messaging to Google Talk. This allows users to send messages to their contacts, even if they are not signed in. They will receive the messages when they next go online even if the user who has sent it is offline.
On June 30, 2006, Nokia released new software for their Nokia 770 Internet Tablet, that included Google Talk as one of the compatible VoIP clients, because of the XMPP-based software. Another Google Talk-compatible device is Sony's mylo, released on September 15, 2006. A Google Talk client is also available for BlackBerry devices from the Blackberry site. Google Talk support is also integrated in Google Android devices.
However, given that Google Talk provides XMPP protocol, most mobile phones for which a suitable XMPP client exists could also offer Google Talk service, at least theoretically (depending on the handset, the user may encounter security warnings because of unsigned J2ME midlets or limits put in place by the mobile service provider). Mobile clients specially designed for Google Talk exist as well.
Most phones support the IMPS protocol, and there are hybrid XMPP/IMPS networks (through XMPP transports, or specially designed hybrid servers), which can also contact GoogleTalk users. The Google Talk service itself is unusable from IMPS (that means, you cannot log with your Gmail account, but you can talk with your Gmail friends with your IMPS account from your mobile phone).
For most smartphones, including Symbian-based as well as Android, third-party applications such as Nimbuzz and Fring include support for Google Talk accounts, including VoIP calls, an option not offered by the Google-provided client in Android.
The idea of an XMPP-based Google IM service was proposed by Eoban Binder on the website Applexnet.com on August 23, 2004.
Exactly one year later, after the rumor of a Google-branded "communications tool" service had been reported by The New York Times and detailed by the Los Angeles Times on August 22, 2005, the subdomain talk.google.com was found to have an active XMPP server. Two methods of logging into the server were discovered soon after and the ensuing response by eager bloggers revealed to numerous others how to login before the official release by Google.
On the evening of August 23, many logged-in users using port 5222 to connect were disconnected and unable to log back in. Users using port 5223 to connect were still able to log in, and at 04:12:52 UTC those users received a broadcast instant message from gmail.com, an apparently official username used by Google to communicate with their user base, that stated "The broken link has been fixed. Thanks for being our first users!" Port 5222-connectivity was found to have been re-enabled. On August 24, Google Talk was officially launched.
On December 15, 2005, Google released libjingle, a C++ library to implement Jingle, "a set of extensions to the IETF's Extensible Messaging and Presence Protocol (XMPP) for use in voice over IP (VoIP), video, and other peer-to-peer multimedia sessions." Libjingle is a library of the code that Google uses for peer-to-peer communication, and was made available under a BSD license.
On February 7, 2006, Gmail added the ability to chat with a built-in XMPP client.
On March 14, 2007, Google released the Google Talk Gadget, an Adobe Flash-based Talk module that can be added to iGoogle (formally the Google Personalized Homepage) or embedded in any web page, thus, allowing one to chat from any operating system which is supported by Adobe Flash Player as long as Adobe Flash Player is installed.
On November 26, 2007, Google Talk released Group Chat capabilities. Prior to this, users could only chat with one person per window. Group chat allows many users to chat with each other in an environment similar to IRC.
On December 6, 2007, Google upgraded its Gmail integrated chat to include AOL Instant Messenger chat capability. This allows Gmail users to sign into the AIM chat service and communicate with any AIM user while still being signed on to the Google Talk service. The Google Talk gadget and client have not been upgraded to enable this feature yet, and no announcement has been made as to when it will be made available.
On February 25, 2008, Google added a feature called chatback, which allows a Google Talk account owner to chat with people who don't have one. The account owner first has to create a badge, which can be included in webpages. This badge shows the current availability of the owner. Clicking on the badge results a chat request notification to the owner who can respond by clicking on the specified URL. During the conversation both parties have to use the Google Talk Gadget and both parties remain anonymous to each other, even the Google Account name of the owner is not revealed to the other peer.
On November 11, 2008, Google Chat (voice and video chat) was launched: it became possible PCs and Intel-based Macs.
Google has released a new version of Google Talk called "Google Talk, Labs edition." It still currently lacks many features of Google Talk's 'stable' releases. The features it lacks include File Sharing and Voice Chat. It features rounded alerts for new email. It can have multiple tabs with group chat, private chat and the regular screen open at once. It is available for free download here: http://www.google.com/talk/labsedition/. Flash Player will be required to install, and upon first launch, a new flash-plugin will need to be downloaded. This edition is not meant for general use, hence the reason why it is a labs edition. Labs edition also includes Google Update service.
Additionally as part of Google's and eBay's Multi-Year Agreement on August 28, 2006, it was announced that the companies will look into making Google Talk users able to communicate with Skype: "The companies will also explore interoperability between Skype and Google Talk via open standards to enable text chat and online presence."
A screen shot was posted on May 18, 2007 as part of the Google Apps presentation, showing some phone integration in Google Talk. A Google engineer confirmed they have been using it internally for some time on March 2, 2008.