Viber requires that you have it set up on a mobile phone before it can be installed on your computer.  This is because your phone number is used to contact you in both places. Viber will ask for the phone number of the device that it was set up on previously.  Once you’ve typed it in, it will send a four digit code to the Viber app on your mobile device.  Type it in and the set up process will be complete. Clicking the Call button will start a voice call.  Users with a webcam can choose to make a video call by pressing the Video button.  To send a text, type your message at the bottom of the window, and click Send. Just like in the mobile app, you’re able to choose who you’d like to include in your conversation by clicking each name.  A check will appear next to everyone included.  Once you’ve chosen all the recipients, click Start Conversation.

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Write a summary of the previous text in Chinese:
在Viber主页下载PC版或Mac版的Viber软件，并进行安装。 打开程序并开始安装过程。 选择列表中的联系人进行短信、电话或视频联系。 点击短消息来打开与某人或多人的消息框。 <finished>