On Demand allows you to stream movies, TV shows, and other content in real time, whenever you want. The service allows you start watching an event as soon as you order it, and then watch it again as many times, as you want in the following 24 to 48 hours.
In addition, many channels make their programming available on demand. If you are subscribed to such a channel in your lineup, you can watch its on-demand offering at no extra charge.
Pay-per-view events air at specific times. You can order concerts, sports events and other Pay-per-view programming in advance, but you have to wait until the event's scheduled start time to watch it.