GTalk

Just when you thought the Internet was filling his time messagingclients, came to Google Talk. Introduced in 2005, Google Talk is an application that allows users to send messages to each other. Unlike Gmail, Google Talk is not based entirely on the Web. Users must first download the application to their own computer to access the full set of features.
These features go beyond a simple message. You can send unlimited files - limited sizes - to other users. Remember, if you choose to send someone large files, it will take time to transfer to other users, mainly through slower connections. So if you have a ceiling on how much data can transfer over your network, you can cope with high cost of Internet service provider (ISP).
Google Talk also has the customer voice over Internet protocol (VOIP). This means you can make PC to PC calls to other Google Talk users. You and your contacts will either need a microphone and speakers, but Google Talk handle the rest. voice in real time can take many ofbandwidth. Just as file transfer, you may be risks arising out of the lid of your data with your ISP if you use this feature much.
Users can also download the Google Talk gadget, a Web application that allows users to access many (but not all) features of Google Talk from personal websites such as blogs or iGoogle pages. This means you can use a computer connected to the Internet to navigate to the appropriate site and use Google Talk. Currently, using Google Talk Gadget is the easiest way Mac owners can access all the features of Google Talk.

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