Gmail helps you stay in touch in a variety of ways. Its offerings range from its basic function email to more advanced features such as phone calls and video chatting. To send an email or chat via text on Gmail, you don't need to do anything more than create an account. Before you can start video chatting with your Gmail contacts, however, you must install the required software.
Visit the Google Voice installation page (link below). http://www.google.com/chat/video
Click the blue "Install voice and video chat" button. When the process is complete, you see a page congratulating you on installing Google voice and video chat. Click the "Gmail" link on this page to go to your Gmail account. Hover your mouse over an online Gmail contact in your contact list. Click "Chat" in the list that appears. This opens a chat with the contact in question in the lower right corner of your Gmail screen. Click the small video camera icon within the chat window to initiate a video chat. Before the chat begins, your contact must accept the video call. You and the person you're calling must have webcams. Most modern laptops come with built-in webcams, and peripheral webcams are available at computer stores.