Instant replay is used to some degree in almost every major professional sport. Most often associated with professional sports such as football, basketball and hockey, instant replay also is used in baseball, tennis, auto racing and golf. Many other professional sports, including rugby, cricket, field hockey and rodeo, also use replay technology. Even professional soccer, which as of 2012 had resisted any pushes to implement instant replay to assist the officials during matches, uses replay to help determine whether disciplinary sanctions are necessary because of actions taken during matches.
The use of instant replay on television broadcasts of professional sporting events had become widespread by the late 1960s. This allowed the broadcasters and everyone who was watching on television to see when mistakes had been made in the officiating or judging of the sporting events. In 1978, the National Football League (NFL) in the United States began studying whether replay technology could be used to review and correct officials' calls during games. The first use of instant replay by a professional sports league, however, was by a competing league — the United States Football League (USFL) — in 1985. As more and more sporting events became televised on a regular basis, thus making replays of all of the action available, other professional sports also began adopting replay systems that could be used in the officiating of their events.
There generally are three ways that instant replay is used in sports. In some cases, a video official looks for any disputable calls, watches the replay, then corrects the regular officials' decisions, if necessary. Other times, participants or coaches are allowed to dispute certain calls, and an official or video official will then watch the replay to determine whether a call was correct. There also might be times when the officials themselves will review the action on a replay before making a call or to confirm or change a call that was made. Some professional sports might allow any or all of these methods in certain instances.
Most professional sports restrict the use of instant replay to certain types of calls or for a limited number of instances within a single event. In the NFL, for instance, only certain types of plays — such as those on which possession of the ball is in question — can be challenged by a coach, and only two or three plays can be challenged by each coach in a game. Professional basketball leagues typically permit replays to be used to determine whether a shot was taken before the game clock or shot clock expired and to determine whether a made basket was a 2-pointer or 3-pointer. In most professional sports, different leagues or organizations around the world have their own rules about the use of replay technology, so its application can vary in specific instances.
The Fédération Internationale de Football Association (FIFA), which is soccer's governing body, had not approved the use of instant replay during matches as of 2012. FIFA uses video evidence only for disciplinary reasons after matches. The organization has long held the position that mistakes by officials are part of the human element of the game. FIFA has, however, authorized some limited testing of video or computerized systems that could help determine whether goals have been scored.