Voice over Internet Protocol (VOIP), is an internet-based phone system, as opposed to a land line that relies on old copper-wire technologies that have been around for a hundred years. With VOIP, users still use a phone handset but they can also use their computer or tablet to deliver and receive voice calls. Because VoIP phone systems work through the internet, unlike traditional PBX (Private Branch Exchange - which is a private telephone network used within a company or organization) systems that rely on landlines, users have access to other handy office features such as messaging, virtual meetings and conferencing.