A VoIP USB phone looks like cordless phone which comes with USB connector. You connect that into the USB port found on your computer or laptop. It is plug-and-play VoIP device that improves your PC to phone calls experience.
So, you do not need a headset or microphone when you use a USB phone.
The following diagram demonstrates it with Skype's soft-phone...
You will find different types and designs of USB phones in the market. Let me mention two manufacturers for now:
Magic-Jack by YMAX Corporation you probably have heard about this device, it is the latest and advanced device. We can say the best and smartest solution until now.
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