National Football League

NFL logo

The National Football League (NFL) is the largest professional American football league, consisting of thirty-two teams from American cities and regions. The league's teams are divided into two conferences: the American Football Conference (AFC) and the National Football Conference (NFC). Each conference is then further divided into four divisions consisting of four teams each, labeled East, West, North, and South.

During the league's regular season, each team plays 16 games over a 17-week period generally from September to January. At the end of each regular season, six teams from each conference play in the NFL playoffs, a 12-team single-elimination tournament that culminates with the NFL championship, the Super Bowl. This game is held at a pre-selected site which is usually a city that hosts an NFL team or a popular college stadium. One week later, selected all-star players from both the AFC and NFC meet in the Pro Bowl, currently held in Hawaii.

Formed in 1920 as the American Professional Football Association (it adopted the name National Football League in 1922), the NFL is one of the major professional sports leagues of North America. It also has by far the highest per-game attendance of any domestic professional sports league in the world; its 2005 attendance of 67,593 per game was over 25,000 higher than the 2005-06 per-game attendance of the league in second place, the Bundesliga in German football (soccer).

The NFL's greatest spurt in popularity came in the 1960s and 1970s after the 1958 NFL Championship Game (which went into overtime); and the emergence of the rival American Football League (AFL) (1960-1969), and the NFL's eventual merger with it in 1970. Prior to the 1960s, the most popular version of American football was played collegiately, with many players opting to play in the Canadian Football League after graduation because they were offered larger sums of money and benefits during that era.

Locations of teams in the NFL

States with AFC team (red), NFC team (blue)

The league has offices in two cities. The main office is in New York City. And due to the popularity of the NFL in the South there is a secondary office located in Nashville, Tennessee.

Teams

There are currently thirty-two NFL clubs. The NFL is the only organization among the four major professional sports leagues of North America to have all of its teams in the United States; MLB and the NBA each have one team in Canada, while the NHL has six teams in that country.

Most major cities in the United States have one NFL franchise, with the striking exception of the second largest city, Los Angeles, which currently does not have one either in the city or its metro area. The NFL is able to utilize the possible relocation of a franchise to Los Angeles as a threat, for example when trying to persuade local governments to contribute to the cost of new stadiums for its other franchises. In a league of its own, The Economist, April 27, 2006. The Washington Redskins are the most lucrative NFL franchise and are actually the most lucrative sports team of all U.S. professional sports, valued at approximately $1.3 billion [1].

American Football Conference
Division	Team	Stadium	City/Area
East	Buffalo Bills	Ralph Wilson Stadium	Orchard Park, New York (Buffalo area)
	Miami Dolphins	Dolphin Stadium	Miami Gardens, Florida (Miami area)
	New England Patriots	Gillette Stadium	Foxborough, Massachusetts (Boston area)
	New York Jets	Giants Stadium	East Rutherford, New Jersey (New York City area)
North	Baltimore Ravens	M&T Bank Stadium	Baltimore, Maryland
	Cincinnati Bengals	Paul Brown Stadium	Cincinnati, Ohio
	Cleveland Browns	Cleveland Browns Stadium	Cleveland, Ohio
	Pittsburgh Steelers	Heinz Field	Pittsburgh, Pennsylvania
South	Houston Texans	Reliant Stadium	Houston, Texas
	Indianapolis Colts	RCA Dome	Indianapolis, Indiana
	Jacksonville Jaguars	ALLTEL Stadium	Jacksonville, Florida
	Tennessee Titans	LP Field	Nashville, Tennessee
-	West	Denver Broncos	INVESCO Field	Denver, Colorado
Kansas City Chiefs		Arrowhead Stadium	Kansas City, Missouri
Oakland Raiders		McAfee Coliseum	Oakland, California
San Diego Chargers		Qualcomm Stadium	San Diego, California
National Football Conference
Division	Team	Stadium	City/Area
East	Dallas Cowboys	Texas Stadium	Irving, Texas (Dallas area)
	New York Giants	Giants Stadium	East Rutherford, New Jersey (New York City area)
	Philadelphia Eagles	Lincoln Financial Field	Philadelphia, Pennsylvania
	Washington Redskins	FedExField	Landover, Maryland (Washington, D.C. area)
North	Chicago Bears	Soldier Field	Chicago, Illinois
	Detroit Lions	Ford Field	Detroit, Michigan
	Green Bay Packers	Lambeau Field	Green Bay, Wisconsin
	Minnesota Vikings	Metrodome	Minneapolis, Minnesota
South	Atlanta Falcons	Georgia Dome	Atlanta, Georgia
	Carolina Panthers	Bank of America Stadium	Charlotte, North Carolina (Carolinas)
	New Orleans Saints	Louisiana Superdome	New Orleans, Louisiana
	Tampa Bay Buccaneers	Raymond James Stadium	Tampa, Florida
-	West	Arizona Cardinals	Cardinals Stadium	Glendale, Arizona (Phoenix area)
St. Louis Rams		Edward Jones Dome	St. Louis, Missouri
San Francisco 49ers		Monster Park	San Francisco, California
Seattle Seahawks		Qwest Field	Seattle, Washington

Season structure

Exhibition season

Summers see most NFL teams playing four "pre-season" exhibition games from early August through early September. Two "featured" exhibition games, the Pro Football Hall of Fame Game and American Bowl, do not count toward the normal allottment of four games, so the four teams playing in those games each end up playing five exhibition games.

The exhibition games are unpopular with many season ticket holders who point out that regular-season prices are charged for meaningless games, in which teams seldom play their stars and starters for more than a quarter of each game. Such complaints have gone all the way to the U.S. Supreme Court, but have failed to change the policy. A judgment in 1974Examples of Exhibition Game Lawsuits stated: "No fewer than five lawsuits have been instituted from Dallas to New England, each claiming that the respective National Football League (NFL) team had violated the Sherman Act by requiring an individual who wishes to purchase a season ticket for all regular season games to buy, in addition, tickets for one or more exhibition or preseason games."

Pro football is so popular that fans pay the price of the exhibition games for the right to have a guaranteed seat during the season. Several exhibition games are broadcast nationally, while local affiliates often pick up the rest of the home team's games.

Regular season

The NFL season begins the weekend after Labor Day. Each team plays 16 games during a 17-week period. Traditionally, every game is played on Sunday afternoon with the exception of one game each week being played on Sunday night, and another game being played on Monday night, known as Monday Night Football. For the last few weeks of the regular season (after the NCAA football regular season has concluded), the league typically schedules two or three nationally-televised games on Saturday afternoons or evenings.

In addition, the Dallas Cowboys and the Detroit Lions each traditionally host a game on Thanksgiving Day. Starting in 2006, a third game is scheduled during that same day in primetime.

Since the 2002 season, the league has scheduled a nationally televised regular season game on the Thursday night prior to the first Sunday of NFL games to kick off the season.

During the 1994 and 2005 seasons when Christmas fell on a Sunday, the NFL flipped their normal schedule for that weekend, having the normal slate (less the Sunday night contest) of Sunday games on Saturday (Christmas Eve day).

Currently, each team's regular season schedule is set using a pre-determined formula: NFL scheduling formula at NFL.com
*Each team plays the other three teams in their division twice: once at home, and once on the road (six games).
*Each team plays once the four teams from another division within its conference on a rotating three-year cycle: two at home, and two on the road (four games).
*Each team plays once the four teams from a division in the other conference on a rotating four-year cycle: two at home, and two on the road (four games).
*Each team plays two games versus two teams within its conference based on the prior year's standings. These games match a first-place team against the first-place teams in the two same-conference divisions the team is not scheduled to play that season. The second-place, third-place, and fourth-place teams in a conference are matched in the same way each year: one at home, and one on the road.

Since debuting in 2002, this formula has been regarded as very successful, rekindling old rivalries and starting new ones, as all teams will play in every other team's stadium at least once every eight years.

For the 2006 season, the assignments are the following:
For the 2007 season, the assignments will be:

Flexible-scheduling

Starting with the 2006 season, the NFL will use a "flexible-scheduling" system for the last seven weeks of the regular season. The system is designed so that the league has the flexibility in selecting games to air on Sunday night that will feature the current hottest, streaking teams.

Under this system, Sunday games to be played during the affected weeks will tentatively have the start time of 1:00 p.m. ET/10:00 a.m. PT, 4:00 p.m. ET/1:00 p.m. PT, or 4:15 p.m. ET/1:15 p.m. PT. On the Tuesday 12 days before the games, the league will move one game to the primetime slot, and possibly move one or more 1:00 p.m. ET slotted games to the 4:00 p.m. ET slots. During the last week of the season, the league could re-schedule games as late as six days before the contests so that all of the television networks will be able to broadcast a game that has playoff implications. Both FOX and CBS will be allowed to broadcast a doubleheader that week.

Sixteen-game schedule

In its early years after 1920, the NFL did not have a set schedule, and teams played as few as eight and as many as sixteen games, some against college or other amateur squads. From 1926 through 1946, they played from eleven to fifteen games per season, depending on the number of teams in the league. From 1947 through 1960, each NFL team played 12 games per season. In 1960, the American Football League began play and introduced a balanced schedule of 14 games per team over a fifteen week season, in which each of the eight teams played each of the other teams twice, with one bye week. Competition from the new league caused the NFL to expand and follow suit with a fourteen-game schedule in 1961. From 1961 through 1977, the NFL schedule consisted of fourteen regular season games played over fourteen weeks. Opening weekend typically was the weekend after Labor Day, or even two weekends after Labor Day. Teams played six, or even seven exhibition games. In 1978, the league changed the schedule to include sixteen regular season games and four exhibition games. From 1978-1989, the sixteen games were played over sixteen weeks.

In 1990, the NFL introduced a bye-week to the schedule. Each team would play sixteen regular season games over seventeen weeks. One week during the season, on a rotating basis, each team would have the weekend off. As a result, opening weekend was moved up to Labor Day weekend. In 1993, the league adjusted the schedule to include two bye weeks per team, and the sixteen games were played over eighteen weeks. In 1994, the schedule was changed back to seventeen weeks.

In 2001, the NFL decided to move opening week to the weekend after Labor Day. Television ratings seemed to be sagging due to the holiday, and the stadium crowds were apparently lacking due to vacationing fans and higher average temperatures of early September. In addition, it would leave the three-day holiday weekend alone to the opening weekend of college football, preventing conflicts, and maximizing exposure. In 2002, the NFL began scheduling a Thursday night special opening game, which would be nationally televised. Festivities and a pre-game concert would kick off the season.
*In 1999, the NFL moved the first week of the season one week later due to the conflict with January 1, 2000. The Year 2000 problem sparked travel concerns for the final week of the season, and playoffs. By moving the season a week later, the NFL hoped to prevent teams traveling complications.
*For most years, there has been an open weekend between the Conference Championship games and the Super Bowl. In the 1990 season, there was no bye, as the league was still adjusting the schedule from adding the bye week during the season. In the 1993 season, there was no bye week since the regular season consisted of eighteen weekends. In the 1999 season, the bye week was removed to accommodate the schedule being moved ahead one week. In the 2001 season, the bye week disappeared when the league moved opening weekend a week later. As a result, Super Bowl XXXVI had to be delayed after the league postponed the second week's games following the September 11 attacks. By the 2003 season, the bye week was restored. In the 1982 strike-shortened season, a postseason tournament replaced the traditional playoff format. The Super Bowl bye week was removed to accommodate the longer, expanded playoffs.

Playoffs

At the conclusion of each 16-game regular season, six teams from each conference qualify for the playoffs, a single-elimination tournament, which culminates in the Super Bowl:
*The four division champions from each conference (the team in each division with the best regular season won-lost-tied record), which are seeded one through four based on their regular season won-lost-tied record.
*Two wild card qualifiers (those non-division champions with the conference's best won-lost-tied percentages), which are seeded five and six.

The third- and the sixth-seeded teams, and the fourth and the fifth seeds face each other, respectively, during the first round of the playoffs, dubbed the Wild Card Playoffs. The first and the second seeds from each conference receive a bye in the first round, which entitles these teams to automatically advance to the second round, the Divisional Playoff games (even though the participants may be from different divisions) to face the Wild Card survivors. In any given playoff round, the highest surviving seed always plays the lowest surviving seed. And in any given playoff game, whoever has the higher seed gets the home field advantage (i.e. the game is held at the higher seed's home field).

The two surviving teams from the Divisional Playoff games meet in the NFC Championship and the AFC Championship games, with the winners of those contests going on to face each other in the Super Bowl.

The terms "Wild Card Playoffs" and "Divisional Playoffs" originated from the playoff format that was used before 1990. During that time, three division winners and two wild card teams from each conference qualified for the playoffs. Only the wild card teams played during the first round, while all of the division winners received a bye, automatically advancing to the second round.

A major disadvantage that critics cite in the current system is that a divisional winner could host a playoff game against a wild card team that earned a better regular season record. For example, the Jacksonville Jaguars finished the 2005 regular season with a 12-4 record, but only qualified as a wild card team and thus had to face the New England Patriots, the AFC East division champions with a 10-6 record, at the Patriots' home field, Gillette Stadium.

Tiebreaking rules

The league uses a set of rules to break ties in the final season standings, i.e. teams that have the same regular season won-lost-tied record. As mentioned above, each team's order of finish in their respective divisions (first-place, second-place, etc.) determine the opponents in two of their games during the following season. The tiebreaking rules are also used to help determine playoff seedings and the order in which teams pick in the NFL draft (see below).

The process basically involves comparing a set of each team's season statistics, one record at a time, until one club has a higher value than the others. The first criterion that is always compared first is head-to-head, how the tied teams fared when they played each other during the regular season. Other data that is then compared include their record against teams in their division, their record against teams in their conference, their record against common opponents, net points scored, and net touchdowns scored. If the teams remain tied after comparing all of these statistics, then the tie is broken using a coin toss. To date, a coin toss has never been used by the league to break a tie.

The tiebreaking rules have changed over the years, with the most recent changes being made in 2002; record vs. common opponents and most of the other criteria involving wins and losses were moved up higher in the tiebreaking list, while those involving compiled stats such as points for and against were moved to the bottom.

League championships

The NFL's method for determining its champions has changed over the years. For the history of the process see National Football League championships.

The draft

Every year during the offseason, each NFL franchise seeks to fill its position needs by adding new players through a process known literally as "the NFL Annual Player Selection Meeting", which is more commonly known as the NFL Draft. The NFL Draft is a highly organized and formal process (currently consisting of seven rounds) that takes place over two days in a weekend in late April, in which all NFL teams participate. The team with the worst record in the previous year gets first pick of each round in the draft (that is, the team is the first to select a player from a pool of all eligible college players in the country), while the winner of the Super Bowl has the last pick in every round. The idea is that weak teams can thereby become strengthened over time, in the specialties where they need strengthening. Draft picks continue, in the order from the weakest team to the strongest team, and once all teams have picked one player, they all pick again starting with the weakest team.

The overwhelming majority of players selected in the draft are NCAA football players, although a few athletes have ben drafted by teams through the years who had not played college football, or who had excelled in other sports such as track, wrestling, basketball, baseball or soccer. In order for a college athlete to be eligible to be drafted, three years must have elapsed since his high school graduation.

Draft picks are frequently traded in advance for players and other draft picks. For example, before the draft occurs, Team A might trade its first-round draft pick plus a certain player (who already plays for Team A) to Team B in exchange for another particular player who already plays for Team B.

Occasionally a player drafted out of college will go right into a "first-string" position as the team's primary player in that position. However, these players usually begin as second- or third-string backups, only playing games if the first-stringer is injured, or if there has been a runaway score and the coach decides to put a backup in the game for a little experience, and to ensure his first-stringer does not get injured at the end in a play that is not meaningful to the team.

Salaries and the salary cap

The minimum salary for an NFL player is $260,000 in his first year, and rises after that based on the number of years in service. Exhibition game minimum is $10,000. These numbers are set by contract between the NFL and the players' union, the National Football League Players' Association. These numbers are of course exceeded dramatically by the best players in each position.

Years Experience	Minimum Salary
0	$260,000
1	$305,000
2	$380,000
3	$455,000
4-6	$540,000
7-9	$665,000
10+	$765,000

Escalating player salaries throughout the 1980s and the advent of free agency in 1992 led to the NFL's adoption of a salary cap in 1994, a maximum amount of money each team can pay its players in aggregate. The cap is determined via a complicated formula based on the revenue that all NFL teams receive during the previous year. For the 2004 season, the NFL's salary cap was $80.582 million, an increase of $5.5 million from 2003. The cap for the 2005 season was set at $85.5 million, and at $102 million for 2006 instead of the previously estimated $94.5 million.

Proponents of the salary cap note that it prevents a well-financed team in a major city from simply spending giant amounts of money to secure the very best players in every position and thus dominating the entire sport. This has been seen as a problem in American baseball, long dominated since the advent of free agency by large market teams. They point to the relative parity of competition that exists in the NFL as of 2005 compared to Major League Baseball as evidence that the NFL salary cap preserves competitive balance. They claim fans end up paying higher ticket prices to help pay for escalating player salaries. These concerns, among others, led in part to modified salary cap adoption in the National Basketball Association in 1984 and the National Hockey League in 2005.

Critics of the salary cap note that the driving reason for the cap was to maximize the profitability of the NFL teams, and limit the power of NFL players to command the high salaries they are said to deserve in exchange for bringing in large numbers of paying fans to the stadiums. Furthermore, they attribute NFL competitive parity instead to the league's extensive revenue sharing policies.âˆ'A new CBA (collective bargaining agreement) was reached between the NFL and the NFLPA on March 8, 2006, which extends the current agreement through 2013. The cap for 2006 was expected to be set at $94.5 million, but due to the new deal it instead was set at $102 million.â†'

Racial policies

Although the current NFL is well-represented at virtually every position by African-American athletes, that was not always the case. The league had a few African American players until 1933, one year after entry to the league of George Preston Marshall. Marshall's policies not only excluded blacks from his Washington Redskins team but may have influenced the entire league to drop African American until 1946, when pressure from the competing All-America Football Conference induced the NFL to be more liberal in its signing of African Americans. Another theory holds that the NFL, like most of the United States during the Great Depression, simply fired African American workers before white workers, but this could hardly account for the league's apparent "all-white" policy during this period. Still, Marshall refused to sign African American players until threatened with civil rights legal action by the Kennedy administration in 1962, in which it was explained to him that his lease on the then-new D.C. Stadium, which was at the time controlled by the United States Department of the Interior, would be voided if he continued to refuse to sign any African American players. This action, and pressure by another competing league, the more racially-liberal American Football League, slowly managed to reverse the NFL's racial quotas. The AFL's Denver Broncos were the first modern-era team to have a African American starting quarterback, Marlin Briscoe, who started the fourth game of the 1968 season, and broke pro football rookie records for passing yardage and touchdowns. The next year 1969, another American Football League team, the Buffalo Bills were the first professional football team of the modern era to begin the season with an African American, James Harris as their starting quarterback. The Chicago Bears had an African American quarterback in 1953, Willie Thrower, who played in only one game and did not start in any games. After that, no old-line NFL team had an African American starting quarterback until the Steelers' Joe Gilliam in 1972.

Even after that, for many NFL teams the door would remain closed to African American quarterbacks through the 1970s. 1978 Rose Bowl MVP Warren Moon played for six seasons in the CFL before his abilities finally landed him the starting role with the Houston Oilers. It took until 1988 before an African American quarterback started for a Super Bowl team, when Doug Williams won it for the Redskins. To this day, the NFL's head-coach hiring policies are questioned, and it has had to institute measures to attempt to have African American head coach candidates be treated more equitably.

White skill players have become increasingly rare in the modern NFL, as most positions are filled by African Americans. White running backs, defensive backs, and receivers have become less and less common over the last 25 years. In 2005, a slim majority of offensive linemen are white, while no whites are listed as Tailbacks or Cornerbacks on NFL rosters. Most quarterbacks, punters, and kickers are white, while almost all running backs, wide receivers, defensive backs, defensive linemen, safeties, punt returners, and kickoff returners are African American. Increasingly, positions such as tight end, fullback, and linebacker are being filled by African Americans. In the early 1980s, African Americans and whites each made up roughly half of the players. Since then, the percentage of African American players has increased steadily to its present 2005 level of 69%. Whites make up the majority of the remaining players, followed by Pacific Islanders, Hispanics, and Asians.

Television

The television rights to the NFL are the most lucrative (and most expensive) rights of any American sport available. In fact, it was television that brought pro football into prominence in the modern era of technology. Since then, NFL broadcasts have become among the most-watched programs on American television, and the fortunes of entire networks have rested on owning NFL broadcasting rights. As television revenue is shared equally between the teams, the NFL can be viewed as a cooperative organization owned by its members (team owners).

Currently, three broadcast networks and two cable channels televise NFL games: NBC and ESPN own the rights to broadcast games on Sunday and Monday nights, respectively. The NFL Network holds the rights to televise selected contests on Thursday night and Saturday during the second half of the season. For the rest of the games, FOX broadcasts all NFC teams while CBS all AFC teams. For interconference games, FOX televises them if the visiting team is from the NFC and CBS carries them when the visitors are from the AFC.

Radio

Each NFL team has its own radio network and employs its announcers. Nationally, the NFL is heard on the Westwood One Radio Network and on Sports USA Radio. Westwood One carries Sunday and Monday Night Football, all Thursday games, two Sunday afternoon contests and all post-season games, including the Pro Bowl. Sports USA Radio broadcasts two Sunday afternoon games every Sunday during the regular season.

The NFL also has a contract with Sirius Satellite Radio, which provides news, analysis, commentary and game coverage for all games.

History

National Football League logo (1960-1969)

Like the American college football game from which it sprung, NFL football is a descendant of rugby football, which was imported to the United States from Canada in 1874, and then transformed into American college football after McGill University in Montreal invited Harvard University to Quebec to play a new Canadian version of "rugby football". Professional football in the United States dates at least to 1892, when an athletic club in Pittsburgh paid William "Pudge" Heffelfinger $500 to take part in a game. Over the next few decades, while most attention was paid to football at elite colleges on the East Coast, the professional game spread widely in the Midwest, particularly in Ohio where in 1903 the Massillon Tigers, a strong amateur team, hired four Pittsburgh pros to play in their season-ending game against Akron.

The American Professional Football Association was founded in 1920 at a Hupmobile dealership in Canton, Ohio. Legendary athlete Jim Thorpe was elected president. The group of 11 teams, all but one in the Midwest, was originally less a league than an agreement not to rob other teams' players. In the early years, APFA members continued to play non-APFA teams.

In 1921, the APFA began releasing official standings, and the following year, the group changed its name to the National Football League. However, the NFL was hardly a major league in the '20s. Teams entered and left the league frequently. Franchises included such colorful representatives as the LaRue, Ohio Oorang Indians, an all-Native American outfit that also put on a performing dog show.

Yet as former college stars like Red Grange and Benny Friedman began to test the professional waters, the pro game slowly began to increase in popularity. By 1934 all of the small-town teams, with the exception of the Green Bay Packers, had moved to or been replaced by big cities. One factor in the league's rising popularity was the institution of an annual championship game in 1933.

By the end of World War II, pro football began to rival the college game for fans' attention. The spread of the T formation led to a faster-paced, higher-scoring game that attracted record numbers of fans. In 1945, the Cleveland Rams moved to Los Angeles, becoming the first big-league sports franchise on the West Coast. In 1950, the NFL accepted three teams from the defunct All-America Football Conference, expanding to 13 clubs.

In the 1950s, pro football finally earned its place as a major sport. The NFL embraced television, giving Americans nationwide a chance to follow stars like Bobby Layne, Paul Hornung, Otto Graham, and Johnny Unitas. The 1958 NFL championship in New York drew record TV viewership and made national celebrities out of Unitas and his Baltimore Colts teammates.

The rise of professional football was so fast that by the mid-'60s, it had surpassed baseball as Americans' favorite spectator sport in some surveys. As more people wanted to cash in on this surge of popularity than the NFL could accommodate, a rival league, the American Football League (AFL), was founded in 1960.

The AFL introduced features that the NFL did not have, such as wider-open passing offenses, players' names on their jerseys, and an official clock visible to fans so that they knew the time remaining in a period (the NFL kept time by a game referee's watch, and only periodically announced the actual time). The newer league also secured itself financially after it established the precedents for gate and television revenue sharing between all of its teams, and network television broadcasts all of its games.

The AFL also forced the NFL to expand: The Dallas Cowboys were created to counter the AFL's Dallas Texans. The Texans moved the franchise to Kansas City as the Chiefs in 1963; the Minnesota Vikings were the NFL franchise given to Max Winter for abandoning the AFL; and the Atlanta Falcons franchise went to Rankin Smith to dissuade him from purchasing the AFL's Miami Dolphins.

The ensuing costly war for players between the NFL and AFL almost derailed the sport's ascent. By 1966, the leagues agreed to merge as of the 1970 season. The ten AFL teams joined three existing NFL teams to form the NFL's American Football Conference. The remaining 13 NFL teams became the National Football Conference. Another result of the merger was the creation of an AFL-NFL Championship game that for four years determined the so-called "World Championship of Professional Football". After the merger, the then-renamed Super Bowl became the NFL's championship game.

In the 1970s and '80s, the NFL solidified its dominance as America's top spectator sport and its important role in American culture. The Super Bowl became an unofficial national holiday and the top-rated TV program most years. Monday Night Football, which first aired in 1970 brought in high ratings by mixing sports and entertainment. Rules changes in the late '70s ensured a fast-paced game with lots of passing to attract the casual fan.

The founding of the United States Football League in the early '80s was the biggest challenge to the NFL in the post-merger era. The USFL was a well-financed competitor with big-name players and a national television contract. However, the USFL failed to make money and folded after three years.

In recent years, the NFL has expanded into new markets and ventures. In 1991, the league formed the World League of American Football, (now NFL Europe), a developmental league now with teams in Germany and the Netherlands. The league played a regular-season NFL game in Mexico City in 2005 and intends to play more such games in other countries. In 2003, the NFL lauched its own cable-television channel, NFL Network.

Franchise relocations and mergers

In the early years, the league was not stable and teams moved frequently. Franchise mergers were popular during World War II in response to the scarcity of players.

Franchise moves became far more controversial in the late 20th century when a vastly more popular NFL, free from financial instability, allowed many franchises to abandon long-held strongholds for perceived financially greener pastures. While owners invariably cited financial difficulties as the primary factor in such moves, many fans bitterly disputed these contentions, especially in Cleveland, Baltimore and St. Louis, each of which eventually received teams some years after their original franchises left (the Browns, Ravens, and the Rams respectively).

Additionally, with the increasing suburbanization of the U.S. shifting of franchises from the central city to the suburbs became popular from the 1970s on, though at the turn of the millennium a reverse shift back to the central city became somewhat evident.

Video games

Seattle Seahawks running back Shaun Alexander on the cover of Madden NFL 07 for Xbox

Electronic Arts publishes an NFL video game for current video game consoles and for PCs each year, called Madden NFL, being named after former coach and current football commentator John Madden. Prior to the 2005-2006 football season, other NFL games were produced by competing video game publishers, such as 2K Games and Midway Games. However, in December 2004, Electronic Arts signed a five-year exclusive agreement with the NFL, meaning only Electronic Arts will be permitted to publish games featuring NFL team and player names.

Commissioners and presidents

#President Jim Thorpe (1920-1921)[2]#President Joseph Carr (1921-1939)#President Carl Storck (1939-1941)#Commissioner Elmer Layden (1941-1946)#Commissioner Bert Bell (1946-1959)#Interim President Austin Gunsel (1959-1960, following death of Bell)#Commissioner Alvin "Pete" Rozelle (1960-1989)#Commissioner Paul Tagliabue (1989-2006)#Commissioner Roger Goodell (2006-present)

Main League offices

*Canton, Ohio (1920-1921)
*Columbus, Ohio (1921-1941)
*Chicago (1941-1946)
*Philadelphia (1946-1960)
*New York City (1960-present)

Players

*List of American football players
*Current NFL players

Coaches

*Current NFL coaches

Numbering System

The Number System is a system by which players in the NFL wear uniform numbers based on the position they play. It was instituted into the league on April 5, 1973, as a means for officials (referees, linesmen) to more easily identify players on the field by their position.

Number allocations

* Quarterbacks: 1-19
* Running backs: 20-49
* Wide receivers: 10-19, 80-89
* Tight ends: 80-89, 10-19 or 40-49 if all are taken
* Centers: 50-59, 60-79 if all are taken
* Offensive linemen: 60-79
* Defensive linemen: 60-79 and 90-99
* Linebackers: 50-59 and 90-99
* Defensive backs: 20-49
* Placekickers and punters: 1-19

Until 2004, wide receivers were allowed to only wear numbers in the 80s. The NFL changed the rule that year to allow wide receivers to wear numbers 10-19 to allow for the increased amount of retired numbers, as well as more players at wide receiver and tight end (who also wear numbers in the 80s) coming into the league. Keyshawn Johnson started the trend when he wore number 19 in 1996 because the New York Jets had run out of numbers in the 80s. In addition, the first three wide receivers taken in the 2004 NFL Draft - Larry Fitzgerald, Roy Williams, and Reggie Williams - all wear number 11. At the beginning of the 2005 season, 30 wide receivers had numbers in the teens, including prominent players Plaxico Burress (17, New York Giants), Braylon Edwards (17, Cleveland Browns) and Randy Moss (18, Oakland Raiders).

New Orleans Saints RB Reggie Bush petitioned the NFL to let him keep the number 5 which he used at USC. His request was later denied. This has opened debates as to possibly changing the current numbering system to a more flexible one, perhaps mirroring the college rules.

Although centers are supposed to wear numbers 50-59, they usually end up wearing 60-79, due to high amounts of linemen. It's actually little-known that centers are supposed to wear numbers 50-59, since they're usually seen wearing an offensive line number.

Rules named after players

Throughout the league's history, a number of rules have been enacted largely because of a single player's exploits on the field. The following is a partial list of such rule changes:
*the Adam Vinatieri rule -- the clock stops immediately after a field goal is kicked through the uprights. Enacted in 2002 after the Patriots' kicker won Super Bowl XXXVI on a last second kick that went through with two seconds remaining on the clock. The clock didn't stop and New England won.
*the Bronko Nagurski rule

 -- no hands to the facemask by offensive linemen.

*the Fran Tarkenton rule -- a line judge was added as the sixth official to ensure that a back was indeed behind the line of scrimmage before throwing a forward pass. Enacted in 1965.
*the Jerome Bettis rule -- the coin toss must be called before the coin is tossed. Enacted immediately after an incident during the 1998 Thanksgiving Day game between the Steelers and Lions.
*the Ken Stabler rule -- on fourth down or any down in the final two minutes of play, if a player fumbles, only the fumbling player can recover and/or advance the ball. A defensive player can recover and advance at any time of play. Enacted in 1979.
*the Kimo von Oelhoffen rule -- defenders must take every opportunity to avoid hitting a quarterback below the waist when the quarterback is in a defenseless position looking to throw with both feet on the ground. Enacted after the Steelers' defensive lineman tackled Bengals' quarterback Carson Palmer at the knees following a long pass completion during the 2005 playoffs, sending Palmer to the sidelines with multiple ligament tears with a potentially career-ending injury.
*the Lester Hayes rule -- no Stickumâ„¢ allowed. Enacted in 1981.
*the Lou Groza rule -- no artificial medium to assist in the execution of a kick. Enacted in 1956.
*the Mel Blount rule -- Officially known as defensive pass interference, defensive backs can only make contact with receivers within five yards of the line of scrimmage. Enacted in current form in 1978.
*the Mel Renfro rule -- allows a second player on the offense to catch a tipped ball, without a defender subsequentlly touching it. Enacted in 1978.
*the Michael Irvin rule -- no taunting. Another rule, resulting in offensive pass interference, prohibiting WRs to push off CBs, is also often called "the Michael Irvin rule."
*the Bert Emanuel rule -- no "foreign objects" on a player's uniform (enacted in response to the 2002 "Sharpieâ„¢ incident"), though existing rules already forbade this.
*the Ty Law rule
* NFL's Economic Model Shows Signs of Strain
* Professional Football Researchers Association - detailed descriptions of why many of the rules named after players were enacted.
*Process of game-time decisions will eliminate TV duds, create chaos by Michael Hiestand, USA Today, April 5, 2006 (Last accessed April 5, 2006)