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Google Voice is a telecommunications service by Google
launched on March 11, 2009. Google Voice had some 1.4 million users in October 2009, 570,000 of which used the service 7 days a week.

The service is configured and maintained by the user in a web-based application, styled after Google's e-mail service, Gmail. Google Voice currently provides free PC-to-PC voice and video calling worldwide between users of the Google Voice and Video Chat browser plugin (available for Windows, Intel-based Mac OS X, and Linux), and free PC-to-phone calls into North America (this service will remain free at least until the end of 2011).

Google Voice users resident in the US may also make low-cost calls to international phone numbers. For incoming calls, users must have an established US telephone service to activate a Google Voice phone number. Users must configure this and optionally, additional phone numbers that ring simultaneously when the Google Voice number receives a call. The user may answer and receive the call on any of the ringing phones. The service provides a US phone number, chosen by the user from available numbers in selected area codes, free of charge to each user account. Inbound calls to this number are forwarded to other phone numbers of the subscriber. Outbound calls may be placed to domestic and international destinations from the web-based application or by dialing the Google Voice number. Domestic and outbound calls to the US (including Alaska and Hawaii) and Canada are currently free of charge. International calls are billed according to a schedule posted on the Google Voice website. Google Voice provides additional features such as voicemail, call history, conference calling, call screening, blocking of unwanted calls, and voice transcription to text of voicemail messages. Received calls may be moved between configured telephones during a call.

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