The UFC was started as a tournament to find the world's best fighters irrespective of their style, and was based upon Brazilian vale tudo fighting. Although there was a limited number of rules, the UFC was initially known as no holds barred fighting and contests were often violent and brutal. Early UFC fights were less sport than spectacle, which led to accusations of brutality and "human cockfighting" by opponents. Political pressures eventually led the UFC into the underground, as pay-per-view providers nixed UFC programming, nearly extinguishing the UFC's public visibility.

As political pressure mounted, the UFC reformed itself, slowly embracing stricter rules, becoming sanctioned by athletic commissions, and marketing itself as a legitimate sporting event. Dropping the no holds barred label and carrying the banner of mixed martial arts, the UFC has emerged from its political isolation to become more socially acceptable, regaining its position in pay-per-view television. With a cable television deal and legalization of MMA in California, a hotbed for MMA fandom, the UFC is currently undergoing a remarkable surge in popularity, along with heightened media coverage. UFC programming can now be seen on Spike TV in the United States, as well as in 35 other countries worldwide without a satellite dish and all countries worldwide with a satellite dish.

The concept for a tournament to discover the world's best fighting style was the brainchild of Art Davie, a Southern California based advertising executive. Davie met Rorion Gracie in 1991 while researching martial arts for a marketing client. Gracie operated a Brazilian Jiu-Jitsu school in Torrance, California and the Gracie family had a long history of vale-tudo matches – a precursor of mixed martial arts – in Brazil. Davie became Gracie's student.

In 1992, inspired by the Gracies in Action video series produced by the Gracies featuring various martial arts masters being defeated using Gracie Jiu-Jitsu, Davie proposed an eight-man, single-elimination tournament with a working title of War of the Worlds to Rorion Gracie and John Milius. The tournament would feature martial artists from different disciplines facing each other in no holds barred combat to see which martial art was truly the best which replicated the excitement of the matches Davie saw on those videos. Milius, a noted film director and screenwriter, as well as a Gracie student, agreed to be the event's creative director. Davie drafted the business plan and twenty-eight investors contributed the initial capital to start WOW Promotions with the intent to develop the tournament into a television franchise.

In 1993, WOW Promotions sought a television partner and approached pay-per-view producers TVKO (HBO), SET (Showtime) and Semaphore Entertainment Group (SEG). Both TVKO and SET declined, but SEG – a pioneer in pay-per-view television which had produced such off-beat events as a mixed-gender tennis match between Jimmy Connors and Martina Navratilova – became WOW's partner in May 1993. SEG contacted video and film art director Jason Cusson to design the trademarked "Octagon", a signature piece for the event. Cusson remained the Production Designer through UFC 27. SEG devised the name for the show as The Ultimate Fighting Championship. The two companies produced the first event at McNichols Sports Arena in Denver, Colorado on November 12, 1993. Davie functioned as the show's booker and matchmaker. The television broadcast featured two kickboxers, Patrick Smith and Kevin Rosier; a savage fighter, Gerard Gordeau; a karate expert, Zane Frazier; a shootfighter, Ken Shamrock; a sumo wrestler, Teila Tuli; a professional boxer, Art Jimmerson; and Brazilian Jiu-Jitsu black belt Royce Gracie—Rorion's younger brother who was hand-picked by Rorion himself to represent his family. The show was an instant success, drawing 86,592 television subscribers on pay-per-view to witness Royce Gracie take the first UFC crown. In April 1995, following UFC 5 in Charlotte, North Carolina, Davie and Gracie sold their interest in the franchise to SEG and disbanded WOW Promotions. Davie continued with SEG as the show's booker and matchmaker, as well as the Commissioner of Ultimate Fighting, until December 1997.

A core proposition for the show was to find an answer for sports fans: "Can a wrestler beat a boxer?" As was the case with most martial arts at the time, fighters were typically skilled in just one discipline (e.g., boxing, Judo, or jujutsu) and had little experience against opponents with different skills. Some competitors were also rumored to have inflated their credentials to legitimize their presence. Kimo Leopoldo, for example, was touted in UFC 3 as a "third degree black belt" in taekwondo. Kimo's fighting is best described as freestyle and he holds no such rank.

With no weight classes, fighters often faced significantly larger or taller opponents. For example, Keith "The Giant Killer" Hackney faced Emmanuel Yarborough at UFC 3 with a 9 in (22 cm) height and 400 lb (180 kg) weight disadvantage. Many martial artists believed that technique could overcome these size disadvantages, and that a skilled fighter could use an opponent's size and strength against him; with the 170 lb (77 kg) Royce Gracie winning three of the first four UFC events, the UFC quickly proved that size does not always determine outcome.

Although "There are no rules!" was the tagline, the term was not strictly true; the UFC operated with limited rules. There was no biting, no eye gouging, and techniques such as hair pulling, headbutts and groin strikes were frowned upon, but allowed. In fact, in a UFC 4 qualifying match, two competitors Jason Fairn and Guy Mezger agreed not to pull hair as they both wore pony tails tied back for the match. Additionally, that same event saw a matchup between Keith Hackney and Joe Son in which Hackney unleashed a series of groin shots against Joe Son while on the ground. UFC was similarly characterized, especially in the early days, as an extremely violent sport, as evidenced by a disclaimer in the beginning of the UFC 5 broadcast which warned audiences of the violent nature of the event. A brief appearance of a match in the 1995 film Virtuosity likely did little to change this perception.

The UFC became a hit on pay-per-view and home video almost immediately due to its originality, realism, and wide press coverage, although not all of it favorable. The nature of the burgeoning sport quickly drew the attention of the authorities and UFC events were banned in a number of American states. Senator John McCain (R-AZ), was sent a tape of the first UFC events and immediately found it abhorrent. McCain himself led a campaign to ban Ultimate Fighting, calling it "human cockfighting", and sending letters to the governors of all fifty U.S. states to ban the event. As a result, the UFC was dropped from the major cable pay-per-view distributor Viewer's Choice, and individual cable carriers such as TCI Cable. Thirty-six states enacted laws that banned "no-holds-barred" fighting, including New York, which enacted the ban on the eve of UFC 8, forcing a overnight relocation of the event to Dothan, Alabama. The UFC continued to air on DirecTV PPV, though its audience was minuscule compared to the larger cable pay-per-view platforms of the era.

In response to the criticism, the UFC increased its cooperation with state athletic commissions and redesigned its rules to remove the less palatable elements of fights while retaining the core elements of striking and grappling. Weight classes were introduced at UFC 12; gloves became mandatory and kicks to a downed opponent, hair pulling, and groin strikes were banned at UFC 14. UFC 15 saw more limitations on permissible striking areas: strikes to the back of the neck and head, and small joint manipulations were banned. With five-minute rounds introduced at UFC 21, the UFC gradually re-branded itself as a sport rather than a spectacle.

As the UFC continued to work with state athletic commissions, events were held in smaller U.S. markets, including Iowa, Mississippi, Louisiana, Wyoming and Alabama. SEG could not secure home video releases for UFC 23 through UFC 29 in a period known by some fans as the "Dark days" of the UFC. With other mixed martial arts promotions working towards U.S. sanctioning, the International Fighting Championships secured the first U.S. sanctioned mixed martial arts event, which occurred in New Jersey on September 30, 2000. Just two months later, the UFC held its first sanctioned event, UFC 28, under the New Jersey State Athletic Control Board's "Unified Rules". A spokeswoman for McCain would later state "he's very glad to see the changes" in the sport's safety rules.

The UFC continues its rapid rise from being "an almost unknown promotion" in 2005, to gracing the covers of Sports Illustrated and ESPN The Magazine in May 2007. UFC programming is now shown in 36 countries worldwide, and the UFC plans to continue expanding internationally, running shows regularly in Canada and the United Kingdom, with an office established in the UK aimed to expand the European UFC audience.

On March 27, 2007 The UFC and PRIDE Fighting Championships announced an agreement where the majority owners of the UFC, Frank and Lorenzo Fertitta, would purchase the PRIDE organization. Initial intentions were for both organizations to be separately run but aligned together and there were plans to co-promote supercards featuring champions and top contenders from both organizations. But recent comments by Dana White have indicated that the Pride brand will likely be folded and many former Pride fighters are already being realigned under the UFC brand.

The current rules for the Ultimate Fighting Championship were originally established by the New Jersey Athletic Control Board. The "Unified Rules of Mixed Martial Arts" that New Jersey established has been adopted in other states that regulate mixed martial arts, including Nevada, Louisiana, and California. These rules are also used by many other promotions within the United States, becoming mandatory for those states that have adopted the rules, and so have become the standard de facto set of rules for professional mixed martial arts across the country.

Every round in UFC competition is five minutes in duration. Title matches have five rounds, and non-title matches have three rounds. There is a one minute rest period between rounds.

The UFC currently uses five weight classes:

• Lightweight: 146 to 155 lb (70 kg)
• Welterweight: 156 to 170 lb (77 kg)
• Middleweight: 171 to 185 lb (84 kg)
• Light Heavyweight: 186 to 205 lb (93 kg)
• Heavyweight: 206 to 265 lb (120 kg)

In addition, there are four other weight classes specified in the Unified Rules which the UFC does not currently utilize: Flyweight (under 125 lb, 57 kg), Bantamweight (126 to 135 lb, 61 kg), Featherweight (136 to 145 lb, 66 kg), and Super Heavyweight (above 265 lb, 120 kg). The Bantamweight and Featherweight classes are used in another promotion wholly owned by UFC, World Extreme Cagefighting.

The UFC uses an octagonal caged enclosure, "The Octagon", to stage bouts. Originally, SEG had trademarked The Octagon and prevented other mixed martial arts promotions from using the same type of cage, but in 2001, Zuffa gave their permission for other promotions to use octagonal cages (whilst reserving use of the name "Octagon"). Their rationale was that the young sport needed uniformity in order to continue to win official sanctioning.

The cage is composed of an eight-sided structure, the walls consisting of metal chain-link fencing coated with black vinyl, with a diameter of 11.5 m (38 ft), allowing 9 m (30 ft) of space from point to point. The fence is 1.83 m (6 ft) high. The cage sits on top of a platform, raising it 1.2 m (4 ft) from the ground. It has foam padding around the top of the fence and between each of the eight sections. It also has two entry-exit gates opposite each other.

The mat, painted with sponsorship logos and art, is replaced for each event.

All competitors must fight in approved shorts, without shoes or any other sort of foot padding. Shirts, gis or long pants (including gi pants) are not allowed. Fighters must use approved light gloves (110 to 170 g / 4 to 6 ounces) that allow fingers to grab. These gloves enable fighters to use tremendous punching power with less risk of an injured or broken hand, while providing capability in grabbing and grappling.

Originally the attire for UFC was very open if controlled at all. Many fighters still chose to wear tight-fitting shorts or boxing-type trunks, while others wore long pants or tight wrestling suits. Multi-time tournament champion Royce Gracie wore a Jujutsugi in all his early appearances in UFC.

Source: Wikipedia (www.wikipedia.org)