Pay-per-view (often abbreviated PPV) is the system in which television viewers can purchase events to be seen on TV and pay for the private telecast of that event to their homes. The event is shown at the same time to everyone ordering it, as opposed to video on demand systems, which allow viewers to see the event at any time. Events can be purchased using an on-screen guide, an automated telephone system, or through a live customer service representative. Events include feature films, sporting events, and pornographic movies.