An ISP that uses the facilities and services (servers, switches, backbone, etc.) of a large ISP, but retains its own branding for marketing and billing purposes. Virtual ISPs are often formed to target a specific group, whether by location, profession, language or other subject of common interest. A virtual ISP, also known as an "affinity ISP," might be created for a charity, a church, an entertainer, virtually any group or cause that is popular. After obtaining a sufficient number of customers, a virtual ISP may decide to build its own facilities and operate independently.