Titulo De La Eso

American football

American football, known in the United States simply as football, is a sport played between two teams of eleven with the objective of scoring points by advancing the ball into the opposing team's end zone by running with it or throwing it to a teammate. Points can be scored by carrying the ball over the opponent's goal line, catching a pass thrown over that goalline, kicking the ball through the opponent's goal posts or tackling an opposing ball carrier in his own end zone.
In the United States, the major forms are high school football, college football and professional football. Each of these are played under slightly different rules. High school football is governed by the National Federation of State High School Associations and college football by the NationalCollegiate Athletic Association. The highest level league for professional football is the National Football League.
American football is closely related to Canadian football but with some differences in rules and the field. Both sports can be traced to early versions of association and rugby football.

History
Football resulted from several major divergences from rugby football, most notably therule changes instituted by Walter Camp, considered the "Father of Football”. Among these important changes were the introduction of the line of scrimmage and of down-and-distance rules. In the late 19th and early 20th centuries, game play developments by college coaches such as Eddie Cochems, Amos Alonzo Stagg, Knute Rockne, and Glenn "Pop" Warner helped take advantage of the newlyintroducedforward pass.
The origin of professional football can be traced back to 1892, with William "Pudge" Heffelfinger's $500 contract to play in a game for the Allegheny Athletic Association against the Pittsburgh Athletic Club. Pittsburgh's football circuit became fully professional over the course of the 1890s, culminating in the first professional league, the Major League Baseball-backed NationalFootball League of 1902, which folded after one season. The core of professional football moved westward into Ohio beginning in 1903, where it would remain until a mass dispersal throughout the midwest in the late 1910s. In 1920, the American Professional Football Association was formed as a coalition of teams from regional state associations such as the Ohio League and the New York Pro Football League.The first game was played in Dayton, Ohio on October 3, 1920 with the host Triangles defeating the Columbus Panhandles 14–0. The league changed its name to the National Football League (NFL) two years later; from its inception, the NFL had been the de facto major league of football. Initially a sport of Midwestern industrial towns in the United States, professional football eventually became anational phenomenon. Football's increasing popularity is usually traced to the 1958 NFL Championship Game, a contest that has been dubbed the "Greatest Game Ever Played". A rival league to the NFL, the American Football League (AFL), began play in 1960; the pressure it put on the senior league led to a merger between the two leagues and the creation of the Super Bowl, which has become the mostwatched television event in the United States on an annual basis. Other professional leagues, both major (or at least attempting to be major) and minor, have formed but almost all have been short-lived.
Objectives
American football is played by two teams, so that 11 offensive players one team's defensive play against 11 other teams. The attacking team tries to get the ball either by race or bypassage toward the end zone and score points. The defense has to prevent this from happening and try to stop the advance of the opposing team to the annotation.The game is for the offensive squad achieved a touchdown (worth six points) main goal or field goal (worth 3 points) otherwise. To do so they must move at least ten yards (9.144 meters) in a maximum of four times or downs. For every ten yards...