en.wikipedia.org/wiki/Professional_football_(gridiron)

In the United States and Canada, the term professional football includes the professional forms of American and Canadian gridiron football. In common usage , it ...

en.wikipedia.org/wiki/National_Football_League

The National Football League (NFL) is a professional American football league consisting of 32 teams, divided equally between the National Football ...

en.wikipedia.org/wiki/History_of_American_football

Several other professional football leagues have been formed since the AFL– NFL merger, though none have had ...

www.cbssports.com/nfl/news/from-aaf-to-xfl-to-pacific-pro-football-and-more-heres-a-guide-to-all-the-new-non-nfl-football-leagues

Feb 13, 2019 ... The NFL runs the show when it comes to major professional sports leagues, but these days, it's also one of just a bunch of leagues vying for ...

www.profootballhof.com/football-history/chronology-of-professional-football

The Latrobe Athletic Association football team went entirely professional, becoming the first team to play a full season with only professionals.

www.nfl.com/teams

News · Scores · Schedule · Standings · Draft · NFL 100 · NFL 100 · Fantasy · Game Pass · Super Bowl · Combine · Highlights · Stats · Next Gen Stats · Ways to  ...

www.nytimes.com/2019/02/05/sports/football-new-league.html

Feb 5, 2019 ... The most recent, less than Super Bowl notwithstanding, the N.F.L. continues to be a behemoth, dominating the sports landscape in revenue, ...

www.pro-football-reference.com

Complete source for pro football history including complete player, team, and league stats, awards, records, leaders, rookies and scores.

www.history.com/this-day-in-history/professional-football-is-born

Nov 16, 2009 ... On this day in 1920, seven men, including legendary all-around athlete and football star Jim Thorpe, meet to organize a professional football ...