A hosted IP PBX, or hosted VoIP PBX, is a business-class phone service provided over the internet. This is in contrast to traditional phone service, operated over telephone wires. A hosted IP PBX includes the ability for businesses to manage their own system in an interface like the VirtualPBX Dash interface, displayed here. It also routes incoming calls to the right individuals or teams inside the company and adds standard business phone system features like an auto-attendant or virtual receptionist, business voicemail, call transfers between employees, and more.
The first hosted PBX was in fact not a hosted IP PBX. That first system used the copper wires of the PSTN (Public Switched Telephone Network), to provide a hosted business phone service. It is still in high demand today for companies that don’t want or can’t use internet telephony.