Virtual PBX is a software or a service that runs on a PC or a mobile device and allows users to route calls to different extensions, forward calls to other numbers, and make calls from their computers. Virtual PBX is designed to serve businesses that rely heavily on phone communication. The word "virtual" refers to the "virtual" software on the server dedicated to a specific customer rather than the traditional PBX system in a physical building. Virtual PBX systems operate on computer networks and can be accessed remotely.