What are the most important moments that make up MMA today as we know it?
That is actually impossible to say because MMA as "we" know it, does not exist. MMA exists as we all know it individually.
I am a dedicated and passionate mixed martial arts enthusiast, and these are the top 25 moments that make up MMA today as "I" know it.
Of course, I have not studied martial arts in Japan or fought in Brazil's Vale Tudo circuits, so my knowledge of MMA, like everyone else's, is limited.
What I do know is a good amount about major international mixed martial arts competitions over the past 15 to 20 years, and a good deal about the culture and growth of commercial MMA here in America.
I see MMA as a sport made increasingly legitimate through a series of standout events which have helped build interest off an ancient heritage to a commercially viable practice in global markets, but becoming anchored in Western culture.
In the context of this MMA worldview, these are the top 25 moments in MMA history that have brought us to today.
What top moments define MMA for you?
Disgruntled with the Ultimate Fighting Championships (UFC), legend Dan Henderson left the organization and fought Strikeforce middleweight champion Jake Shields in April 2010.
Shields pulled off the upset by dominating Dan Henderson for Rounds 2 through 5 and earning a clear-cut decision.
The fight was an important reminder that top talent exists outside of the UFC.
Almost as if on cue, the UFC responded by immediately picking up Shields before eventually taking control of the Strikeforce organization.
Ever since Brock Lesnar joined MMA, fans have been skeptical about his contribution.
Regardless of perceptions, Lesnar became far and away the biggest pay-per-view draw in the sport.
In his title defense against Shane Carwin, he proved that he is championship material not due to size and strength alone, but that his technique and ability to overcome adversity are top of the line too.
The legendary heavyweight kickboxer Mirko "Cro Cop" Filipovic had been devastating opponents in MMA, but had yet to attain a championship.
That would change after participating in the 2006 PRIDE Open-Weight Grand Prix.
Cro Cop devastated his opponents in the first two rounds, advancing him to the semifinals, which were to be held on the same day as the finals.
That day was September 10th, 2006.
In one of the most memorable days in MMA history, Mirko Cro Cop took out fellow legends Wanderlei Silva and Josh Barnett to claim the Grand Prix championship.
Cro Cop had stormed through the tournament, finishing every opponent in the first round and winning the championship on his 32nd birthday.
The stone-cold striker was overwhelmed with emotion.
At UFC 71, Quinton "Rampage" Jackson simultaneously solidified himself in MMA's history books and officially ended the Chuck Liddell era.
Liddell's momentum was riding as high as ever and many imagined the matchup against Jackson as merely an opportunity for the champion to avenge a previous career loss.
Jackson proved to be the better man that night and ushered in a new, and more turbulent, era for the UFC's marquee division, light heavyweight.
Many anticipated Liddell's loss would be discouraging for the UFC, but fair competition continues to nurture the sport's growth.
Wanderlei Silva's first victory over Japanese icon and legend Kazushi Sakuraba, in 2001, started Silva's incredible celebrity in Japan.
In total, the two warriors fought three times with Silva stopping Sakuraba each time, including their second bout, which was for Pride's inaugural middleweight (205 lbs) championship.
Chuck Liddell is one of the greatest champions in UFC history and helped usher in a new era of mainstream commercial success during his time at the top of the sport.
His greatest moment was knocking out Randy Couture for a second time in their rubber match at UFC 57.
The fight was the most anticipated in UFC history to that point, and Chuck cemented himself as one of the greatest of all time with an emphatic victory over the fellow legend.
UFC 40 roused interest in MMA among mainstream media outlets unlike any other event before it.
The fight card was stacked with emerging stars like Andrei Arlovski, Robbie Lawler and Chuck Liddell. It also featured two legendary champions in Matt Hughes and Tito Ortiz defending their belts.
Mainstream appeal was still a long ways off, but UFC 40 was an amazing event that encouraged MMA's upward swing.
Matt Hughes was as dominant a champion as there was during his time, taking part in several important and memorable moments for MMA.
I choose his victory over Royce Gracie to represent him on this list as it is as official of a changing of the guard as there has been in MMA.
Gracie was brought back to the UFC to face their champion in a catch-weight super-fight at 175 lbs.
Hughes dominated Gracie for over four minutes, displaying a level of competition far above the pioneer's ability, and the referee was forced to call a stop to the fight at 4:39 of the first round.
Anderson Silva has made a legacy of creating remarkable moments. You could fill an entire list of spectacular moments that are just Anderson Silva victories
Although some had already speculated he might be the best fighter in the world, Silva's most landmark moment was when he proved it against Dan Henderson at UFC 82.
Many thought Henderson would expose Silva's flaws and claim victory.
Not only did Silva defeat Henderson, he submitted him.
The only other people to even stop Henderson, are Silva's jiu-jitsu masters, the Nogueira brothers.
From that fight forward, Silva has ruled the MMA world.
Fedor Emelianenko possessed an impressive record, but was an underdog to dominant heavyweight champion Antonio Rodrigo Nogueira.
The two fighters battled until a decision with Fedor proving to be the victor and Nogueira demonstrating incredible spirit and resilience in defeat.
Emelianenko would never relinquish his championship and the two fighters would continue down successful careers.
They remain the No. 1 and No. 2 heavyweight fighters of all time.
It could be argued that BJ Penn's best moment was finally winning the UFC lightweight championship in 2008 and thus becoming only the second man to have held championships in two different weight divisions (after Randy Couture).
While that is an important milestone, many feel it was not a bigger moment than his career-defining first-round submission victory over Matt Hughes in 2004.
Penn was considered a dangerous fighter, especially at lightweight, but probably not a threat to dominant welterweight champion Hughes.
Right from the opening bell Penn controlled the action and softened Matt Hughes up with some big punches. Before Hughes could even realize what was happening, he was forced to tap to a rear-naked choke.
Penn's domination was shocking and established him as an instantaneous legend.
There are several moments where Randy Couture helped define MMA history, but perhaps none was as great as his first encounter with fellow legend Chuck Liddell.
Randy Couture was a multiple-time UFC heavyweight championship winner, but moved down to light heavyweight and challenged Chuck Liddell for the light heavyweight interim-championship as an underdog.
Couture showcased one of his most vintage miraculous and inspirational underdog victories by upsetting Liddell and TKO'ing him in the third round.
Couture unified his interim belt by defeating Tito Ortiz for the undisputed championship in his next fight, making him the first fighter to ever win UFC championships in two different weight classes.
Dan Henderson was already the Pride welterweight champion (183 lbs), and he moved up in weight to challenge longtime middleweight (205 lbs) champion Wanderlei Silva.
Silva had beat Henderson over six years prior, but this was Henderson's time to shine.
Henderson knocked Silva out cold, becoming the only fighter to ever hold a major world championship in two divisions at the same time.
Kazushi Sakuraba earned the nickname "The Gracie Hunter" by defeating four members of the famous Gracie family.
After defeating Royler and Royce, but before defeating Ryan, Sakuraba battled Renzo Gracie at Pride 10.
Sakuraba locked up a tight Kimura on Renzo, and as per Gracie family tradition, Renzo refused to tap. Renzo's refusal to tap resulted in his arm being grotesquely broken.
The Gracie name was still pivotal in understanding mixed martial arts competition, but their domination weaned and their art struggled to stand up by itself in the face of a burgeoning sport.
When Georges St-Pierre won the welterweight championship in 2006, the entire MMA community figured the young star would not lose for years to come.
In his first title defense, St-Pierre was a huge favorite over Matt Serra.
Matt Serra came out on fire and lit St-Pierre up with punches, finishing him in the first round.
In subsequent fights, St-Pierre rebounded in dominant fashion, but his loss to Matt Serra has gone down in history as the biggest upset of all time.
In May 2007, Roger Huerta became the first mixed martial artist to ever be featured on the cover of famous sports publication Sports Illustrated.
The article discussed the rising popularity of mixed martial arts and was an important milestone for MMA's growth.
When the UFC bought Pride Fighting Championships, many fans and pundits were concerned about the direction that the UFC might take the sport.
Pride, after all, was the UFC's largest competitor, and they had a different philosophy and approach to providing fights.
At UFC 79, fans finally got to see a fight that had been talked about for years in Wanderlei Silva vs. Chuck Liddell, the two former figureheads for their respective organizations.
The fight resulted in an exciting three-round war that delivered the goods for the fans.
Whatever direction the UFC was going to take MMA, fans could breathe a sigh of relief knowing that exciting fights were still the sport's motor.
Pride Final Conflict 2005 might go down as the best MMA event in history.
There was not a single fighter on the card that is not an influential figure in MMA.
Of distinguishing note, Mauricio "Shogun" Rua staked his claim in history by defeating Alistair Overeem and Ricardo Arona in the same night to capture the middleweight (205 lbs) Grand Prix tournament championship.
Also, headlining the event was the heavyweight championship fight between Fedor Emelianenko and Mirko Cro Cop in what many consider to be the most anticipated fight in MMA history up to that point.
After the UFC bought Pride, its largest competitor, fellow US-based company Strikeforce began growing into the No. 2 company.
With high-profile fighters and important media connections, Strikeforce looked primed to become a major alternative to the UFC.
Then in March 2011, Zuffa LLC announced the purchase of Strikeforce.
With a single company running the UFC and Strikeforce, the fate of MMA now seems to be secured in a single set of hands.
Upstart company Bellator appears to be finding some success and growth, but the emergence of another major alternative to Zuffa products seems unlikely.
In late 2006, the UFC announced that they had purchased World Extreme Cagefighting (WEC).
It was a meaningful business event, but not as significant as when Dana White announced that the organization would be merging with the UFC in late 2010.
The move signaled a consolidation of top talent in the sport, and the inclusion of two smaller weight divisions into the sport's spotlight.
The Pride organization debuted with its first event on October 11th, 1997 in Tokyo.
Pride would go on to become the second biggest MMA promotion in history, with a large number of fans preferring Pride's representation of the sport.
Although Pride would not be as financially successful as its American counterpart, the UFC, its events, fighters and fights proved to be some of the most significant in history.
While the brand has since dissipated into the UFC, its influence still resonates loudly.
Some enthusiasts, like outspoken champion Nick Diaz, still herald Pride's rules and qualifications for in-fight engagement and thus criteria for scoring and refereeing.
The main event of Pride 1 featured Nobuhiku Takada vs. Rickson Gracie. Rickson won by armbar.
For more about Pride, go here: Pride Guide
In March of 2007, it was announced that Frank and Lorenzo Fertitta, of Zuffa LLC and the UFC had purchased the rights to Pride Fighting Championships.
The UFC had essentially bought out their biggest rival and threat, ensuring their status as the top dog in the world of mixed martial arts.
Forrest Griffin's war with Stephan Bonnar for the Ultimate Fighter Season 1 finale is the most landmark fight in the history of mixed martial arts.
Their bout was a fight of attrition that exemplified their spirit and willpower, as well as obvious skill.
Most importantly, the exciting battle drove herds of new fans into the sport and actualized MMA as an arena for developing athletes on a large stage and scale.
Before Frank and Lorenzo Fertitta bought the UFC along with Dana White in 2001, the UFC was fledgling financially and politically.
The three men created "Zuffa LLC" to be the parent company for the UFC and turned the organization around.
The time before Zuffa is referred to as the "dark ages" of the UFC. Zuffa implemented weight divisions and rules to protect fighter safety.
By being put in the hands of Zuffa, The Ultimate Fighting Championships became a financially healthy and profitable organization with access to the first real growth opportunities for the sport.
UFC 1 gave birth to MMA, and like all births, it was not pretty and it was bloody. In fact, you can hardly recognize it as MMA when you look back on it.
But when the Gracie family decided to showcase their fighting arts to the world with a big tournament in America, what they were doing was indeed giving birth to a sport.
As the chosen representative for the Gracie family, Royce tore through his opposition in a single day eight-man tournament.
It would take a while for MMA to get its legs underneath it, but here we are now, thanks to Royce Gracie.