National Football League

The National Football League (NFL) is the largest all-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 North, South, East, and West. During the league's regular season, each team plays sixteen games over a seventeen-week period, generally from September to December. At the end of each regular season, six teams from each conference play in the NFL playoffs, a twelve-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. Two weeks later, selected all-star players from both the AFC and NFC meet in the Pro Bowl, currently held in Honolulu, Hawaii. The NFL was formed in 1920 as the American Professional Football Association and adopted the name National Football League in 1922. The NFL is one of the most popular sports leagues in the United States, and has the highest per-game attendance of any domestic professional sports league in the world, drawing over 67,000 spectators per game for the 2006 season.

History
{| class="wikitable" style="text-align:center;margin-left:1em;float:right" !width="145" | Team !align="center" width="55" | Titles }
 * + Total NFL championships
 * align="center" | Green Bay Packers
 * 13
 * align="center" | Chicago Bears
 * 9
 * align="center" | Cleveland Browns
 * 8
 * align="center" | New York Giants
 * 7
 * align="center" | Pittsburgh Steelers
 * 6
 * align="center" | San Francisco 49ers
 * 5
 * align="center" | Washington Redskins
 * 5
 * align="center" | Dallas Cowboys
 * 5
 * align="center" | Detroit Lions
 * 4
 * align="center" | Indianapolis Colts
 * 4
 * align="center" | New England Patriots
 * 3
 * align="center" | Oakland Raiders
 * 3
 * align="center" | Philadelphia Eagles
 * 3
 * align="center" | St. Louis Rams
 * 3
 * align="center" | Canton Bulldogs
 * 2
 * align="center" | Denver Broncos
 * 2
 * align="center" | Miami Dolphins
 * 2
 * align="center" | Tennessee Titans
 * 2
 * align="center" | Buffalo Bills
 * 2
 * align="center" | Kansas City Chiefs
 * 2
 * align="center" | Akron Pros
 * 1
 * align="center" | Cleveland Bulldogs
 * 1
 * align="center" | Pottsville Maroons
 * 1
 * align="center" | Frankford Yellow Jackets
 * 1
 * align="center" | Providence Steam Roller
 * 1
 * align="center" | Arizona Cardinals
 * 1
 * align="center" | San Diego Chargers
 * 1
 * align="center" | New York Jets
 * 1
 * align="center" | Baltimore Ravens
 * 1
 * align="center" | Tampa Bay Buccaneers
 * 1
 * align="center" | New Orleans Saints
 * 1
 * 1
 * align="center" | Cleveland Bulldogs
 * 1
 * align="center" | Pottsville Maroons
 * 1
 * align="center" | Frankford Yellow Jackets
 * 1
 * align="center" | Providence Steam Roller
 * 1
 * align="center" | Arizona Cardinals
 * 1
 * align="center" | San Diego Chargers
 * 1
 * align="center" | New York Jets
 * 1
 * align="center" | Baltimore Ravens
 * 1
 * align="center" | Tampa Bay Buccaneers
 * 1
 * align="center" | New Orleans Saints
 * 1
 * 1
 * align="center" | Baltimore Ravens
 * 1
 * align="center" | Tampa Bay Buccaneers
 * 1
 * align="center" | New Orleans Saints
 * 1
 * align="center" | New Orleans Saints
 * 1
 * 1

Early era
The American Professional Football Association was founded in 1920 at a Hupmobile dealership in Canton, Ohio. Legendary athlete Jim Thorpe was elected president. It was the first league of American Football in the United States for which players were paid a salary to participate. The group of eleven 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 1920s. Teams entered and left the league frequently. Franchises included such colorful representatives as the Providence Steam Roller, the Decatur Staleys, and 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 its popularity. By 1934 all of the small-town teams, with the exception of the Green Bay Packers, had moved to or been replaced by teams in big cities. One factor in the league's rising popularity was the institution of an annual championship game in 1933.

1933 was also the year that black players disappeared from the NFL, just after the acceptance into the league of Boston Braves owner George Preston Marshall, who effectively dissuaded other NFL owners from employing black players until the mid-forties, and who kept blacks off his team (which eventually became the Washington Redskins) until he was forced to integrate by the Kennedy administration in 1962.

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 second big-league sports franchise on the West Coast (second to the Seattle Metropolitans in the PCHA). In 1950, the NFL accepted three teams from the defunct All-America Football Conference, expanding to thirteen 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, played in Yankee Stadium but blacked out by league policy 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-1960s, it had surpassed baseball as Americans' favorite spectator sport in some surveys. When the NFL turned down Lamar Hunt's request to purchase either an existing or expansion NFL franchise, he formed the rival American Football League (AFL), in 1960. He encouraged, wheedled, and cajoled seven other like-minded men to form this new league. The group of the eight founders of the AFL teams was referred to as the "Foolish Club." One of them, fellow Texan Bud Adams of Houston, had likewise tried but failed to be granted an NFL franchise. Hunt's goal was to bring professional football to Texas and to acquire an NFL team for the Hunt family. The AFL filed an anti-trust lawsuit against the NFL in 1960, but this was dismissed in 1962.

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 of all of its games. While the NFL virtually ignored small and historically black colleges as a source of player talent, the AFL actively recruited from such schools and AFL teams installed blacks at positions from which they were tacitly excluded in the NFL, such as quarterback and middle linebacker.

One of the seminal civil-rights actions of the 1960s was the boycott by AFL players of the 1964 (January 1965) AFL All-Star Game scheduled for New Orleans, after black players were refused service from cabbies and hotel staff there. The game was successfully moved to Houston. Even though they were AFL players who had accomplished this action, at the Pro Football Hall of Fame in Canton, Ohio, there is a small exhibit detailing the integration of professional football. A brief video clip addresses the boycott and credits the players (and implicitly the National Football League, although at the time it had no involvement with the players) with changing two racial laws in New Orleans.

The AFL also forced the NFL to expand: The Dallas Cowboys were created to counter Hunt's AFL Dallas Texans franchise. 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 thirteen 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.

Modern era
In the 1970s and 1980s, 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. Rule changes in the late 1970s 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 1980s 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. The USFL filed a successful anti-trust lawsuit against the NFL, but the remedies were minimal.

In recent years, the NFL has expanded into new markets and ventures. In 1986, the league began holding a series of pre-season exhibition games, called American Bowls, held at international sites outside the United States. Then in 1991, the league formed the World League of American Football, later known as NFL Europe and still later as NFL Europa, a developmental league that had teams in Germany and the Netherlands when the NFL shut it down in June 2007. 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 launched its own cable-television channel, NFL Network.

The NFL proper has announced that this season, a regular season game between the Miami Dolphins and the New York Giants will be held outside the borders of the United States.

On August 31, a story in USA Today unveiled the first changes to the league's shield logo since 1980, which will take effect with the 2008 season. The redesign reduces the number of stars in the logo from 25 (which were found not to have a meaning beyond decorative) to eight (for each of the league's divisions), the logo's football repositioned in the manner of the Vince Lombardi Trophy, and the NFL letters in a straight serifed font (which resembles the current typeface used in other NFL logos). The redesign was created with television and digital media, along with clothing in mind.

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 (the Rams and the Browns), Baltimore (the Colts), Houston (the Oilers) and St. Louis (the Cardinals), each of which eventually received teams some years after their original franchises left (the Browns, Ravens, Texans and the Rams respectively). However, Los Angeles, the second-largest media market in the United States, has not had an NFL team since 1994 after both the Raiders and the Rams relocated elsewhere.

Additionally, with the increasing suburbanization of the U.S., the building of new stadiums and other team facilities in the suburbs instead of the central city became popular from the 1970s on, though at the turn of the millennium a reverse shift back to the central city became somewhat evident.

Exhibition season
Following mini-camps in the spring and officially recognized Training Camp in July-August, NFL teams typically play four exhibition games (referred to by the NFL as "pre-season games"; the league discourages the use of the term "exhibition game") from early August through early September. Two "featured" pre-season games, the Pro Football Hall of Fame Game and American Bowl, do not count toward the normal allotment of four games, so the four teams playing in those games each end up playing five exhibition games.

The games are useful for new players that are not used to playing in front of very large crowds. Management often uses the games to evaluate newly signed players. Veteran starters will generally play only for about a quarter of each game so they can avoid injury.

Playoffs


The season concludes with a 12-team tournament used to determine the teams to play in the Super Bowl. The tournament brackets are made up of six teams from each of the league's two conferences, the American Football Conference (AFC) and the National Football Conference (NFC), following the end of the 16-game regular season:


 * The four division champions from each conference (the team in each division with the best regular season won-lost-tied record), which are seeded 1 through 4 based on their regular season won-lost-tied record.
 * Two wild card qualifiers from each conference (those non-division champions with the conference's best won-lost-tied percentages), which are seeded 5 and 6.

The 3 and the 6 seeded teams, and the 4 and the 5 seeds, face each other during the first round of the playoffs, dubbed the Wild Card Playoffs (the league in recent years has also used the term Wild Card Weekend). The 1 and the 2 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, 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 Conference Championship games, with the winners of those contests going on to face one another in the Super Bowl.

Television
The television rights to the NFL are the most lucrative and expensive rights not only of any American sport, but of any American entertainment property. With the fragmentation of audiences due to the increased specialization of broadcast and cable TV networks, sports remain one of the few entertainment properties that not only can guarantee a large and diversified audience, but an audience that will watch in real time.

Annually, the Super Bowl often ranks among the most watched shows of the year. Four of Nielsen Media Research's top ten programs are Super Bowls. Networks have purchased a share of the broadcasting rights to the NFL as a means of raising the entire network's profile.

Under the current television contracts, which began during the 2006 season, regular season games are broadcast on five networks: CBS, FOX, NBC, ESPN, and the NFL Network. Regionally shown games are broadcast on Sundays on CBS and FOX, carrying the AFC and NFC teams respectively (the traveling team deciding the broadcast station in the event of inter-Conference games). These games generally air at 1:00 p.m. ET and 4:00 p.m. or 4:15 p.m. ET. Nationally televised games include Sunday night games (shown on NBC), Monday night games (shown on ESPN), the Thursday night NFL Kickoff Game, the annual Dallas Cowboys and Detroit Lions Thanksgiving Day games, and, as of 2006, select Thursday and Saturday games on the NFL network, a wholly owned subsidiary of the National Football League.

Additionally, satellite broadcast company DirecTV offers NFL Sunday Ticket, a subscription based package, that allows most Sunday daytime regional games to be watched. This package is exclusive to DirecTV in the USA. In Canada, NFL Sunday Ticket is available on a per-provider distribution deal on both cable and satellite.

Radio
Each NFL team has its own radio network and employs its announcers. Nationally, the NFL is heard on the Westwood One Radio Network, Sports USA Radio Network and in Spanish on Univision Radio and the United Stations Radio Network. 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, as well as comprehensive coverage of the draft and off-season on its own channel, Sirius NFL Radio.

Internet radio broadcasts of all NFL games are managed through FieldPass, a subscription service. Radio stations are, by rule, prohibited from streaming the games for free from their Web sites; however, there are numerous stations that break this rule. The NFL on Westwood One and the NFL on Sports USA Radio are not available on FieldPass.

Player contracts and compensation
Most of this section is no longer accurate, pending resolution of the 2011 owner's lockout.

NFL players are all members of a union called the National Football League Players Association (NFLPA). The NFLPA negotiates the general minimum contract for all players in the league. This contract is called the Collective Bargaining Agreement (CBA), and it is the central document that governs the negotiation of individual player contracts for all of the league's players. The current CBA has been in place since 1993, and amended in 1998 and again in 2006. The NFL has not had any labor-related work stoppages since the 1987 season, which is much longer than Major League Baseball, the NBA or the NHL. The most recent CBA was due to expire at the end of the 2012 season, bur was voided by the owners in early 2011.

Players are tiered into three different levels with regards to their rights to negotiate for contracts:
 * Players that have been drafted (see below), and have not yet played in their first year, may only negotiate with the team that drafted them. If terms cannot be agreed upon, the players only recourse is to refuse to play ("sit out") until terms can be reached. Players often use the threat of sitting out as a means to force the hands of the teams that drafted them. For example, John Elway was drafted by the Baltimore Colts in 1983 but refused to play for them. He had a fallback option of baseball, as he had played in the New York Yankees organization for two summers while at Stanford. The Colts traded his rights to the Denver Broncos and Elway agreed to play. Bo Jackson sat out an entire year in 1986, choosing to play baseball in the Kansas City Royals organization (and ultimately for the Royals themselves) rather than play for the Tampa Bay Buccaneers who had drafted him. He reentered the draft the following year, and was drafted and subsequently signed with the Los Angeles Raiders.
 * Players that have played between 3–5 full seasons in the league, and whose contract has expired are considered "Restricted Free Agents" (see below). They have limited rights to negotiate with any club.
 * Players that have played 5 or more full seasons in the league, and whose contract has expired, are considered "Unrestricted Free Agents"(see below) and have unlimited rights to negotiate with any club. Teams may name a single player in any given year as a "Franchise Player"(see below), which eliminates much of that players negotiation rights. This is a limited right of the team, however, and affects only a small handful of players each year.

Among the items covered in the CBA are:


 * No salary cap
 * The annual collegiate draft
 * Rules regarding "free agency"
 * Waiver rules

Salaries
A player's salary, as defined by the CBA, includes any "compensation in money, property, investments, loans or anything else of value to which an NFL player may be awarded" excluding such benefits as insurance and pension. A salary can include an annual pay and a one-time "signing bonus" which is paid in full when the player signs his contract. For the purposes of the salary cap (see below) the signing bonus is prorated over the life of the contract rather than to the year in which the signing bonus is paid.

Player contracts are not guaranteed; teams are only required to pay on the contract as long as the player remains a member of the team. If the player is cut, or quits, for any reason, the balance of the contract is voided and the player receives no further compensation.

{| class="wikitable" style="float:right;margin:1em 0 1em 1em" !Years Experience !Minimum Salary

Among other things, the CBA establishes a minimum salary for its players, which is stepped-up as a player's years of experience increase. Players and their agents may negotiate with clubs for higher salaries, and frequently do. As of the 2005 NFL season, the highest paid player was Atlanta Falcons quarterback Michael Vick, whose "cap value" was slightly under $8 million. The overall value of his contract is 10 years at $130 million, averaging $13 million a year, including signing bonuses and annual salary.

Salary cap
The salary cap is defined as the maximum amount that a team may spend on player compensation, (see above) for all of its players combined. Unlike other leagues, for example the NBA (which permits certain exemptions) or Major League Baseball (which has a "soft cap" enforced by "luxury taxes"), the NFL has a "hard cap": an amount no team under any circumstances may exceed.

The NFL salary cap is calculated by the current CBA to be 59.5% of the total projected league revenue for the upcoming year. This number, divided by the number of teams, determines an individual teams maximum salary cap. For 2006, this is approximately $102 million per team. For 2007, it is projected that this will rise to $109 million.

Teams and players often find creative ways to fit salaries under the salary cap. Early in the salary cap era, "signing bonuses" were used to give players a large chunk of money up front, and thus not count in the salary for the bulk of the contract. This led to a rule whereby all signing bonus are pro-rated equally for each year of the contract. Thus a player who receives a $10 million dollar signing bonus for a 5 year contract would count $2 million per year for the life of the contract, even though the full $10 million was paid up front during the first year of the contract. Also, if a team cuts any player, the signing bonus ceases to be pro-rated, and the entire balance of the bonus counts against the cap in the upcoming season. This is not true of a player's salary which terminates when the player is cut.

Player contracts tend to be "back-loaded". This means that the contract is not divided equally among the time period it covers. Instead, the player earns progressively more and more each year. For instance, a player signing a 4-year deal worth $10 million may get paid $1 million the first year, $2 million the second year, $3 million the third year, and $4 million the fourth year. If a team cuts a player after the first year, the final 3 years do not count against the cap. However, the balance of any signing bonus still counts against the team that cut the player, and it counts in full the year after the player is cut.

Demographics of the NFL
As of the beginning of the 2005 season, the players of the NFL were as follows:


 * African American 1,107 or 64.1%,
 * White American 590 or 34.2%,
 * Other Race 31 or 1.8%. Most of the players who fall in this category are Pacific Islanders, with Samoans being especially abundant.

As of the beginning of the 2006 season, the players of the NFL were as follows:


 * African American 1,137 or 65.8%,
 * White American 559 or 32.3%,
 * Other Race 32 or 1.9%.

The NFL Draft
Every year during April, each NFL franchise seeks to add new players to its roster through a collegiate draft known as "the NFL Annual Player Selection Meeting", which is more commonly known as the NFL Draft.

Teams are ranked in inverse order based on the previous season's record, with the worst record picking first, and the second worst picking second and so on. The draft proceeds for 7 rounds. Rounds 1–3 are run on Saturday of draft weekend, rounds 4–7 are run on Sunday. Teams are given a limited amount of time to make their picks. If the pick is not made in the allotted time, subsequent teams in the draft may draft before them. This happened in 2003 to the Minnesota Vikings.

Teams have the option of trading away their picks to other teams for different picks, players, cash, or a combination thereof. While player-for-player trades are rare during the rest of the year (especially in comparison to the other major league sports), trades are far more common on draft day. In 1989, in arguably the most famous draft day trade ever, the Dallas Cowboys traded running back Herschel Walker to the Minnesota Vikings for five veteran players and six draft picks over 3 years. The Cowboys would use these picks to leverage trades for additional draft picks and veteran players. As a direct result of this trade, they would draft many of the stars that would help them win 3 Super Bowls in the 1990s, including Emmitt Smith, Russell Maryland and Darren Woodson.

The first pick in the draft is often taken to be the best overall player in the rookie class. This may or may not be true, since teams often select players based more on needs than on overall skill. Plus, comparing players at different positions is difficult to do. Still, it is considered a great honor to be a first-round pick, and a greater honor to be the first overall pick. The very last pick in the draft is known as Mr. Irrelevant, and is the subject of a dinner in his honor in Newport Beach, California.

Drafted players may only negotiate with the team that drafted them (or to another team if their rights were traded away). The drafting team has one year to sign the player. If they do not do so, the player may reenter the draft and can be drafted by another team. Bo Jackson famously sat out a season in this way.

General
As defined by the CBA, a free agent is any player who is not under contract to any team and thus has fully free rights to negotiate with any other team for new contract terms. Free agents are classified into two categories: restricted and unrestricted. Furthermore, a team may "tag" a player as a franchise or transition, which places additional restrictions on that player's ability to negotiate. However, the ability to "tag" is quite limited, and only affects a handful of players each year.

Free agency in the NFL began with a limited free agency system known as "Plan B Free Agency", which was in effect between the 1989 and 1992 seasons. Beginning with the 1993 season, "Plan A Free Agency" went into effect, which is the system which remains in the NFL today.

Restricted free agent
A player who has 3-5 years of experience is eligible for restricted free agency, whereby his current team has the chance to retain rights to this player by matching the highest offer any other NFL franchise might make to that player. The club can either block a signing or, in essence, force a trade by offering a salary over a certain threshold. In 2006, these thresholds were as follows:
 * If a club tenders an offer of $685,000 per year for a three year veteran, and $725,000 for a four year veteran, the player's current team has "right of first refusal" over the contract at those terms, and may sign the player at those terms.
 * If a club tenders an offer of $712,000 or 110% (whichever is greater) of the previous year's salary, then the current club has both "right of first refusal" and rights to a draft pick from the same round (or better) from the signing club. Essentially, this means that the new club must forfeit the draft pick to the old club if they wish to sign the player under these terms.
 * If a club tenders an offer of $1.552 million or 110% (whichever is greater) of the previous year's salary, then the current club has both "right of first refusal"; and rights to the first round draft pick from the signing club.

Unrestricted free agent
A player who has 5 or more years of experience is eligible for unrestricted free agency, whereby his current team has no guaranteed right to match outside offers to that player. This means that players in this category have unlimited rights to negotiate any terms with any team.

Franchise tag
The franchise tag is a designation given to a player by a franchise that guarantees that player a contract the average of the five highest-paid players of that same position in the entire league, or 120% of the player's previous year's salary (whichever is greater) in return for retaining rights to that player for one year. An NFL franchise may only designate one player a year as having the franchise tag, and may designate the same player for consecutive years. This has caused some tension between some NFL franchise designees and their respective teams due to the fact that a player designated as a franchise player precludes that player from pursuing large signing bonuses that are common in unrestricted free agency, and also prevents a player from leaving the team, especially when the reasons for leaving are not necessarily financial. A team may, at their discretion, allow the franchise player to negotiate with other clubs, but if they sign with another club, the first club is entitled to two first round draft picks in compensation.

Steroid policy
The NFL steroid policy has been acclaimed by some and criticized by others, but the policy is the longest running in professional sports, beginning in 1987. The current steroid policy of the NFL suspends players without pay who test positive for banned substances as it has since 1989: four games for the first offense (a quarter of the regular season), eight games for a second offense (half of the regular season), and 12 months for a third offense. The suspended games may be either regular season games or playoff games. 

In comparison to the steroid policies of Major League Baseball and the National Hockey League, the NFL has long been the most strict. While recently MLB and the NHL decided to permanently ban athletes for a third offense, they have long been resistant to such measures, and random testing is in its infancy. 

Since the NFL started random, year-round tests and suspending players for performance enhancing drugs it has caught many more players using drugs. By April 2005, 111 NFL players had tested positive for performance enhancing drugs, and of those 111, the NFL suspended 54. Only two NFL players have ever tested positive more than once, and they both retired. 

A new rule has been put into effect due to Shawne Merriman. Starting the 2007–2008 season, the new rule prohibits any player caught using performance enhancing drugs from being able to play in the Pro Bowl that year.

Current NFL teams
There are 32 NFL teams. Each club is allowed a maximum of 55 players, though nearly every team keeps only 53 on their final roster in case of injury, during the regular season. Unlike Major League Baseball], Major League Soccer, the National Basketball Association and the National Hockey League, the league has no teams in Canada largely because of the historical existence of the Canadian Football League.

Most major metropolitan areas in the United States have an NFL franchise; the notable exception is the Los Angeles area, from which both the Raiders and Rams relocated following the 1994 season. The NFL is able to utilize the possible relocation of a franchise to Los Angeles as leverage, for example when trying to persuade local governments to contribute to the cost of new stadiums for its other franchises. The Washington Redskins are the most lucrative sports team of all U.S. professional teams, valued at approximately $1.4 billion.

Since the 2002 season, the teams have been aligned as follows:

American Football Conference

 * 1 Original American Football League (AFL) franchise
 * ² AFL expansion franchise (1966)
 * ³ Original AFL franchise, as the Boston Patriots
 * 4 Original AFL franchise, as the New York Titans
 * 5 AFL expansion franchise (1968)
 * 6 Original AFL franchise, as the Houston Oilers
 * 7 Original AFL franchise, as the Dallas Texans
 * 8 Original AFL franchise, as the Los Angeles Chargers
 * 9 NFL franchises moved to the AFC after the AFL-NFL merger

National Football Conference

 * 1 The Dallas Cowboys played at Texas Stadium in Irving, TX prior to 2009.

Video games
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, who commentates the game along with Al Michaels. 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. This prompted video game developer Midway Games to release a game in 2005 called Blitz: The League, with fictitious teams such as the "Washington Redhawks", and make references to NFL players such as the Washington Redhawks left-handed QB "Ron Mexico", alluding to Michael Vick (at the time playing for the Atlanta Falcons), who allegedly used the alias at a walk-in clinic.

Commissioners and presidents

 * 1) President Jim Thorpe (1920–1921)
 * 2) President Joseph Carr (1921–1939)
 * 3) President Carl Storck (1939–1941)
 * 4) Commissioner Elmer Layden (1941–1946)
 * 5) Commissioner Bert Bell (1946–1959)
 * 6) Interim President Austin Gunsel (1959–1960, following death of Bell)
 * 7) Commissioner Alvin "Pete" Rozelle (1960–1989)
 * 8) Commissioner Paul Tagliabue (1989–2006)
 * 9) 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)

Uniform numbers
In the NFL, players wear uniform numbers based on the position they play. The current system was instituted into the league on April 5, 1973, as a means for fans and officials (referees, linesmen) to more easily identify players on the field by their position. Players who were already in the league at that date were grandfathered, and did not have to change their uniform numbers if they did not conform. Since that date, players are invariably assigned numbers within the following ranges, based on their primary position:
 * Quarterbacks, placekickers and punters: 1–19
 * Wide Receivers: 10-19 and 80-89
 * Running backs and defensive backs: 20–49
 * Offensive linemen: 50–79
 * Linebackers: 50–59 and 90–99
 * Defensive linemen: 60–79 and 90–99
 * Tight ends: 80–89, or 40–49 if all are taken

Prior to 2004, wide receivers were allowed to only wear numbers 80–89. The NFL changed the rule that year to allow wide receivers to wear numbers 10–19 to allow for the increased number of players at wide receiver and tight end coming into the league. Prior to that, players were only allowed to wear non-standard numbers if their team had run out of numbers within the prescribed number range. Perhaps most familiar to fans, Keyshawn Johnson began wearing number 19 in 1996 because the New York Jets had run out of numbers in the 80s.

Occasionally, players will petition the NFL to allow them to wear a number that is not in line with the numbering system. Brad Van Pelt, a linebacker who entered the NFL in 1973 with the New York Giants, wore number 10 during his 11 seasons with the club, despite not being covered by the grandfather clause. In 2006, New Orleans Saints running back Reggie Bush petitioned the NFL to let him keep the number 5 which he used at USC. His request was later denied. Former Seattle Seahawks standout Brian Bosworth attempted such a petition in 1987 (to wear his collegiate number of 44 at the linebacker position), also without success. The Seahawks attempted to get around the rule by listing Bosworth as a safety, but after he wore number 44 for a game against the Kansas City Chiefs, the NFL ruled Bosworth would have to switch back to his original number, 55.

It should be noted that this NFL numbering system is based on a player's primary position. Any player wearing any number may play at any position on the field at any time (though players wearing numbers 50–79 must let the referee know that they are playing out of position by reporting as an "ineligible number in an eligible position"). Normally, only players on offense with eligible numbers are permitted to touch the ball by taking a snap from center, receiving a hand-off or catching a pass. It is not uncommon for running backs to line up at wide receiver on certain plays, or to have a large lineman play at fullback or tight end in short yardage situations. Also, in preseason games, when teams have expanded rosters, players may wear numbers that are outside of the above rules. When the final 53-player roster is established, they are reissued numbers within the above guidelines.

Awards

 * Vince Lombardi Trophy
 * Lamar Hunt Trophy
 * George S. Halas Trophy
 * Most Valuable Player
 * Coach of the Year
 * Offensive Player of the Year
 * Defensive Player of the Year
 * Offensive Rookie of the Year
 * Defensive Rookie of the Year
 * Super Bowl MVP
 * NFL Comeback Player of the Year
 * Walter Payton Man of the Year Award
 * Pro Bowl MVP

Discontinued awards

 * AFL All-Star Game MVP
 * UPI NFL MVP
 * UPI NFC Player of the Year
 * UPI AFL-AFC Player of the Year
 * UPI NFL-NFC Rookie of the Year
 * UPI AFL-AFC Rookie of the Year

Pre-seasons

 * American Bowl
 * Pro Football Hall of Fame Game

Regular seasons

 * List of NFL seasons
 * List of NFL tied games (since 1974)
 * National Football League: Last to First
 * Significant rivalries in the NFL
 * NFL Kickoff game
 * Thanksgiving Classic

Postseasons

 * One Game Playoff
 * NFL playoffs
 * AFC Championship Game
 * NFC Championship Game
 * Playoff Bowl (defunct)
 * Super Bowl
 * Pro Bowl
 * History of NFL Championships
 * List of Super Bowl champions
 * List of NFL champions
 * Professional Football Championship Games
 * List of Current NFL franchise post-season droughts
 * Active NFL playoff appearance streaks

Records

 * NFL Standings since AFL-NFL merger
 * NFL opening day standings
 * NFL Individual Records
 * NFL Team-Oriented Records
 * NFL Annual Rushing Leaders

American football

 * American Football League
 * All-America Football Conference
 * NFL Europa
 * List of leagues of American football

Further information

 * "NFL Scores Nearly $18 Billion in TV Rights", by Stefan Fatsis and Kyle Pope, 14 January 1998, The Wall Street Journal (p. B1)
 * 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)
 * Pro Football Reference - Historical stats of every team, player and coach in the NFL.
 * Five NFL teams worth over $1 billion
 * Pro Football Reference - Historical stats of every team, player and coach in the NFL.
 * Five NFL teams worth over $1 billion