The Ultimate Fighter is a reality television series and mixed martial arts (MMA) competition, originating from the United States, and produced by Spike TV and the Ultimate Fighting Championship (UFC). On this show, professional MMA fighters that have yet to make a big name for themselves are situated in a house outside of Las Vegas, Nevada and compete against each other for the title of The Ultimate Fighter, winning a six-figure, multi-fight contract with the UFC.

For the first four seasons, prospect UFC fighters were selected in two weight classes. The fighters are divided into two teams, irrespective of weight class, each team coached by a current UFC headliner. The teams then compete (in a manner which varies by season) to determine which team would have the right to pair one of their own fighters against an opponent of their choice in the same weight class to an MMA match, the loser being eliminated from competition. At the end of a season, the two remaining fighters of each weight class are placed in a single-elimination tournament, where the title of Ultimate Fighter is awarded to the winner. From season five to season seven, all fighters competed in the same weight class.

The show features the daily preparations each fighter makes to train for competition and the interactions they have with each other living under the same roof. Day-to-day events on the show are overseen by UFC president Dana White.

With the exception of the season finales, fights on The Ultimate Fighter are sanctioned by the Nevada Athletic Commission as exhibition matches and do not count for or against a fighter's professional record. This is done to keep the results from going public before the air date.

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