Umpire

A referee or simply ref is the person of authority in a variety of sports who is responsible for presiding over the game from a neutral point of view and making on-the-fly decisions that enforce the rules of the sport, including sportsmanship decisions such as ejection. The official tasked with this job may be known, in addition to referee, by a variety of other titles as well (often depending on the sport), including umpire, judge, arbiter, arbitrator, linesman, commissaire, timekeeper, touch judge or Technical Official (by the International Olympic Committee).

The term referee originated in association football. Originally the team captains would consult with each other in order to resolve any dispute on the pitch. Eventually this role was delegated to an umpire. Each team would bring their own partisan umpire allowing the team captains to concentrate on the game. Later, the referee, a third "neutral" official was added; this referee would be "referred to" if the umpires could not resolve a dispute. The referee did not take his place on the pitch until 1891, when the umpires became linesmen (now assistant referees). Today, in many amateur football matches, each side will still supply their own partisan assistant referees (still commonly called club linesmen) to assist the neutral referee appointed by the governing football association if one or both assistant referees are not provided. In this case, the role of the linesmen is limited to indicating out of play and cannot decide off side.

An umpire is an official in the sport of Australian rules football. Games are overseen by one to three field umpires, two to four boundary umpires, and two goal umpires.

A game of bandy is officiated by a referee, the authority and enforcer of the rules, whose decisions are final. The referee may be assisted by one or two assistant referees.

In baseball and softball, there is commonly a head umpire (also known as a plate umpire) who is in charge of calling balls and strikes from behind the plate, who is assisted by one, two, three, or five field umpires who make calls on their specific bases (or with five umpires the bases and the outfield). On any question, the head umpire has the final call.

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