Voice over Internet Protocol refers to the technology that allows us to make and receive phone calls over the Internet in real time. It is a set of protocols working together to deliver internet telephony functions similar to regular phone lines or PSTN (public switched telephone network). The difference is that VoIP phone service provides flexibility and mobility that is not possible with traditional telephony. By delivering voice calling functions over internet connections, it allows anyone to use Voice over IP from anywhere via their laptops, desktops, or smart devices