In Canadian football, a single (also called a single point, or rouge) is a one-point score that is awarded for certain plays that involve the ball being kicked into the end zone and not returned from it.
A single is awarded when the ball is kicked into the end zone by any legal means—other than a convert (successful or not) or a successful field goal—and the receiving team does not return (or kick) the ball out of its end zone.  A single is also scored if a kick—excluding kickoffs—goes out of bounds in the end zone without being touched.
A single is indicated by the referee raising his right arm and index finger.  After conceding a single, the receiving team is awarded possession of the ball at its 35-yard line (Football Canada rules) or 40-yard line (CFL rules). 
Singles are not awarded in the following situations:
In each of the above cases, the defending team is awarded possession of the ball at its 25-yard line.
In the official rules, the single point is also called a rouge,  French for "red". The origin is unclear.
There is one other way to score one point on a gridiron football play, other than a routine extra point. If either team scores a safety on a conversion attempt after a touchdown, one point is awarded. 
The Canadian Football League (CFL) has discussed abolishing the single, but proposals to do so have been rejected. A 2005 proposal to reduce scenarios resulting in a single on missed field goal attempts was also rejected.  A less-sweeping proposal would see the single eliminated on punts and field goal attempts that travel through the sidelines of the end zone – such a change would eliminate the "consolation" point for a failed coffin corner attempt. Other proposals would have the rouge scored only on kicks scrimmaged from beyond a certain point or are otherwise deemed 'returnable', having touched the end zone or a return team player without being advanced back into the field of play.
The lowest scoring game in CFL history, a 1–0 victory by the Montreal Alouettes over the Ottawa Rough Riders in 1966,  had no scoring except for a single in the fourth quarter on a missed field goal attempt. 
In the CFL and its predecessor leagues, the most rouges ever scored by one kicker in a game is 11, by Ben Simpson of the Hamilton Tigers against the Montreal AAA Winged Wheelers on October 29, 1910.  The final score was 14–7 in favour of Hamilton. However, this was before the modern CFL was founded, and so it does not count as a CFL record.
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In American football, Canadian football-type singles are not used. Receiving teams are allowed to down the ball in the end zone for a touchback, and kicking the ball out of bounds through the end zone also results in a touchback; in either case, the receiving team receives possession of the ball at either its own 20- or 25-yard line, depending on the specific level of play.
Some indoor American football leagues have used the single, namely the National Indoor Football League, the American Indoor Football Association and the Professional Indoor Football League, all now defunct. The single was applied only on kickoffs, and was scored if the receiving team failed to advance the ball out of the end zone when kicked. The NIFL and AIFA also allowed a single to be scored by kicking a kickoff through the uprights (as in a field goal); this type of single was nicknamed (and was later codified in the AIFA rules as) an uno,  from the Spanish word for the number one.
The concept of the rouge dates back to several public school sports played in England from the early 19th century. In Rossall Hockey played at Rossall School, and the Eton field game, both of which are still played, a rouge can be scored after the ball has gone into the local equivalent of the 'end zone' after striking another player. The Sheffield Rules, a 19th-century code of football, also used the rouge as a secondary scoring method, as did the first rules formulated by the Football Association in 1863.  The behind used in Australian rules football is similar in concept to the Canadian single (worth one point whereas goals are worth six), as is the point in Gaelic football, hurling, and camogie (where a ball into the net scores three points, while a ball passing over the crossbar scores one).
Canadian football is a sport played in Canada in which two teams of 12 players each compete for territorial control of a field of play 110 yards (101 m) long and 65 yards (59 m) wide attempting to advance a pointed oval-shaped ball into the opposing team's scoring area.
The end zone is the scoring area on the field, according to gridiron-based codes of football. It is the area between the end line and goal line bounded by the sidelines. There are two end zones, each being on an opposite side of the field. It is bordered on all sides by a white line indicating its beginning and end points, with orange, square pylons placed at each of the four corners as a visual aid. Canadian rule books use the terms goal area and dead line instead of end zone and end line respectively, but the latter terms are the more common in colloquial Canadian English. Unlike sports like association football and ice hockey which require the ball/puck to pass completely over the goal line to count as a score, both Canadian and American football merely need any part of the ball to break the vertical plane of the outer edge of the goal line.
Touch football is an amateur variant of American football and Canadian football in which the basic rules are similar to those of the mainstream game, but instead of tackling players to the ground, the person carrying the ball need only be touched by a member of the opposite team to end a down. It is similar to street football, another amateur variant, however in street football full contact is allowed.
A touchdown is a scoring play in gridiron football. Whether running, passing, returning a kickoff or punt, or recovering a turnover, a team scores a touchdown by advancing the ball into the opponent's end zone. In American football, a touchdown is worth six points and is followed by an extra point or two-point conversion attempt.
In sport, a goal may refer to either an instance of scoring, or to the physical structure or area where an attacking team must send the ball or puck in order to score points. The structure of a goal varies from sport to sport, and one is placed at or near each end of the playing field for each team to defend. For many sports, each goal structure usually consists of two vertical posts, called goal posts, supporting a horizontal crossbar. A goal line marked on the playing surface between the goal posts demarcates the goal area. Thus, the objective is to send the ball or puck between the goal posts, under or over the crossbar, and across the goal line. Other sports may have other types of structures or areas where the ball or puck must pass through, such as the basketball hoop. Sports which feature goal scoring are also commonly known as invasion games.
Gridiron football, also known as North American football, or in North America simply football, is a family of football team sports primarily played in the United States and Canada. American football, which uses 11 players, is the form played in the United States and the best known form of gridiron football worldwide, while Canadian football, which uses 12 players, predominates in Canada. Other derivative varieties include arena football, flag football and amateur games such as touch and street football. Football is played at professional, collegiate, high school, semi-professional, and amateur levels.
In American football, a touchback is a ruling which is made and signaled by an official when the ball becomes dead on or behind a team's own goal line and the opposing team gave the ball the momentum, or impetus, to travel over or across the goal line but did not have possession of the ball when it became dead. Since the 2018 season, touchbacks have also been awarded in college football on kickoffs that end in a fair catch by the receiving team between its own 25-yard line and goal line. Such impetus may be imparted by a kick, pass, fumble, or in certain instances by batting the ball. A touchback is not a play, but a result of events that may occur during a play. A touchback is the opposite of a safety with regard to impetus since a safety is scored when the ball becomes dead in a team's end zone after that team — the team whose end zone it is — caused the ball to cross the goal line.
This is a glossary of terms used in Canadian football. The Glossary of American football article also covers many terms that are also used in the Canadian version of the game.
American and Canadian football are gridiron codes of football that are very similar; both have their origins in rugby football, but some key differences exist between the two codes.
United Indoor Football (UIF) was an indoor football league in the United States that operated from 2005 to 2008. Ten owners from the National Indoor Football League, including one expansion and two from arenafootball2 (af2) took their franchises and formed their own league. The league was based in Omaha, Nebraska.
Gameplay in American football consists of a series of downs, individual plays of short duration, outside of which the ball is dead or not in play. These can be plays from scrimmage – passes, runs, punts, or field goal attempts – or free kicks such as kickoffs and fair catch kicks. Substitutions can be made between downs, which allows for a great deal of specialization as coaches choose the players best suited for each particular situation. During a play, each team should have no more than 11 players on the field, and each of them has specific tasks assigned for that specific play.
A kickoff is a method of starting a drive in gridiron football. Additionally, it may refer to a kickoff time, the scheduled time of the first kickoff of a game. Typically, a kickoff consists of one team – the "kicking team" – kicking the ball to the opposing team – the "receiving team". The receiving team is then entitled to return the ball, i.e., attempt to advance it towards the kicking team's end zone, until the player with the ball is tackled by the kicking team, goes out of bounds, scores a touchdown, or the play is otherwise ruled dead. Kickoffs take place at the start of each half of play, the beginning of overtime in some overtime formats, and after scoring plays.
In gridiron football, the safety or safety touch is a scoring play that results in two points being awarded to the scoring team. Safeties can be scored in a number of ways, such as when a ball carrier is tackled in his own end zone or when a foul is committed by the offense in their own end zone. After a safety is scored in American football, the ball is kicked off to the team that scored the safety from the 20-yard line; in Canadian football, the scoring team also has the options of taking control of the ball at their own 35-yard line or kicking off the ball, also at their own 35-yard line. The ability of the scoring team to receive the ball through a kickoff differs from the touchdown and field goal, which require the scoring team to kick the ball off to the scored upon team. Despite being of relatively low point value, safeties can have a significant impact on the result of games, and Brian Burke of Advanced NFL Stats estimated that safeties have a greater abstract value than field goals, despite being worth a point less, due to the field position and reclaimed possession gained off the safety kick.
A field goal (FG) is a means of scoring in gridiron football. To score a field goal, the team in possession of the ball must place kick, or drop kick, the ball through the goal, i.e., between the uprights and over the crossbar. The entire ball must pass through the vertical plane of the goal, which is the area above the crossbar and between the uprights or, if above the uprights, between their outside edges. American football requires that a field goal must only come during a play from scrimmage while Canadian football retains open field kicks and thus field goals may be scored at any time from anywhere on the field and by any player. The vast majority of field goals, in both codes, are place kicked. Drop kicked field goals were common in the early days of gridiron football but are almost never done in modern times. In most leagues, a successful field goal awards three points.
A return specialist or kick returner is a player on the special teams unit of a gridiron football team who specializes in returning punts and kickoffs. There are few players who are exclusively return specialists; most also play another position such as wide receiver, defensive back, or running back. The special teams counterpart of a return specialist is a kicking specialist.
In gridiron football, a two-point conversion or two-point convert is a play a team attempts instead of kicking a one-point conversion immediately after it scores a touchdown. In a two-point conversion attempt, the team that just scored must run a play from scrimmage close to the opponent's goal line and advance the ball across the goal line in the same manner as if they were scoring a touchdown. If the team succeeds, it earns two additional points on top of the six points for the touchdown, for a total of eight points. If the team fails, no additional points are scored.
In sports, out of bounds refers to being outside the playing boundaries of the field. Due to the chaotic nature of play, it is normal in many sports for players and/or the ball to go out of bounds frequently during a game. The legality of going out of bounds, and the ease of prevention, vary by sport. In some cases, players may intentionally go or send the ball out of bounds when it is to their advantage.
In gridiron football, a punt is a kick performed by dropping the ball from the hands and then kicking the ball before it hits the ground. The most common use of this tactic is to punt the ball downfield to the opposing team, usually on the final down, with the hope of giving the receiving team a field position that is more advantageous to the kicking team when possession changes. The result of a typical punt, barring any penalties or extraordinary circumstances, is a first down for the receiving team. A punt is not to be confused with a drop kick, a kick after the ball hits the ground, now rare in both American and Canadian football.
The conversion, try, or convert occurs immediately after a touchdown during which the scoring team is allowed to attempt to score one extra point by kicking the ball through the uprights in the manner of a field goal, or two points by bringing the ball into the end zone in the manner of a touchdown.