Instant replay or action replay is a video reproduction of something that recently occurred which was both shot and broadcast live. The video, having already been shown live, is replayed in order for viewers to see again and analyze what had just taken place. Some sports allow officiating calls to be overturned after the review of a play. Instant replay is most commonly used in sports, but is also used in other fields of live TV. While the first near-instant replay system was developed and used in Canada, the first instant replay was developed and deployed in the United States.