Pay-per-view (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, like the WWE 24/7 system.
The term “Pay-per-view” in wrestling terms is the word used for special televised events, usually 3 hours long. The PPVs are considered the hightlight of the federation, the best matches and the culmination of feuds and storylines. It's where the big world title matches take place and they are usually hyped on television in the weeks and months leading up to the event.
WWE PPVs are almost always held in major cities, with top-drawing cities such as New York City, Chicago, Los Angeles, Boston, St. Louis, Philadelphia, Miami, Phoenix, Detroit, and Houston usually getting a PPV just about once every year.