Question: How many martial arts are Olympic sports?

Karate at the Summer Olympics


Karate will make its debut appearance at the Summer Olympics in 2020 in Tokyo, Japan.
Olympic karate will feature two events, Kumite and Kata. Sixty competitors from around the world will compete in the Kumite competition and twenty will compete in the Kata competition. Both divisions of the competition will be split 50/50 between men and women.[1][2]
Background
The quest to bring karate to the Olympics was begun in the 1970s by Jacques Delcourt.[3][4][5][6]
In 2009, in the 121st International Olympic Committee voting, karate did not receive the necessary two-thirds majority vote to become an Olympic sport.[7] Karate was being considered for the 2020 Olympics,[8]however at a meeting of the IOC's executive board, held in Russia on May 29, 2013, it was decided that karate (along with wushu and several non-martial arts) would not be considered for inclusion in 2020 at the IOC's 125th session in Buenos Aires, Argentina, in September 2013.[9]
Bid for inclusion
In September 2015, karate was included in a shortlist along with baseball, softball, skateboarding, surfing, and sport climbing to be considered for inclusion in the 2020 Summer Olympics;[10] and in June 2016, the Executive Board of the International Olympic Committee (IOC) announced that they would support the proposal to include all of the shortlisted sports in the 2020 Games.[11] Finally, on August 3, 2016, all five sports (counting baseball and softball together as one sport) were approved for inclusion in the 2020 Olympic program.[12]
Format and rules
The Olympic karate competition will put eight gold medals in dispute: six for the Kumite (fight) competition (with three weight categories for each sex) and two for the Kata (form) competition (one for each sex).
The main rules for Kumite and Kata competitions are as follows:
Kumite
The individual tournament for the Kumite competition at the World Karate Federation (WKF) Karate World Championships is held under a weight class system comprising five divisions each for both men and women.[13] However, the Kumite competition at the Summer Olympics will consist of just three divisions each, thus:
Weight classes for men: −67kg, −75kg, +75kg
Weight classes for women: −55kg, −61kg, +61kg[14]
Kumite rules
In any category, fights last for up to three timed minutes (i.e. the clock stops every time the referee says yame). During that period, the winner is considered to be the karateka who scores eight points more than their adversary. If this does not happen, the person with more points at the end of the fight is the winner. If the fight ends up tied, a decision by the judges determines the winner – there are four side judges plus the referee.[15]
Assignment of points
Points are earned as follows:
Ippon (three points): for hitting the head or neck of the opponent with a kick, or when any technique is applied to a fallen adversary.
Waza-ari (two points): for applying a kick to the belly, side, back or torso of the opponent.
Yuko (one point): for delivering a punch with open hand (uchi) or closed hand (tsuki) to the head, neck, belly, side, back or torso of the opponent.
Strikes below the belt are strictly forbidden and strength must always be controlled as the fighter will receive a warning if they hurt their opponent, points may be lost or there may even be a disqualification if the resulting injury is severe. Knocking an opponent down to the floor without at least attempting to strike him/her is also liable to be punished.
Points can be lost as follows:
Chukoku (first warning): for committing a minor infraction for the first time. As this is only the first warning, points are not awarded to the adversary.
Keikoku (second warning): for the same minor infraction, or for committing a medium infraction for the first time. One point is awarded to the adversary.
Hansoku-chui (third warning): for committing the same minor infraction for the third time, the same medium infraction for a second time, or for committing a major infraction for the first time (usually excessive contact to vital parts or below the belt, really hurting the opponent). The victory is given to the opponent.
Hansoku (fourth and final warning): this not only gives victory to the opponent but makes it an 8−0 victory, inflicting serious damage on the team score as a whole. It is only given for very serious infractions and usually results in future punishments to the athlete, such as a banishment or suspension.
Warnings and punishments are divided into two different categories, the first being for excessive and/or illegal contact and the other for technical violations, such as leaving the koto (fighting space) or faking an injury in order to make the referee give the opponent a warning.
Kata
Competitors are judged on the speed and power of their techniques. Under conventional competition rules, one competitor is assigned a blue belt and the other a red belt, and each takes a turn in demonstrating his or her kata. The outcome of the competition is determined under a flag system, where five judges who each have a blue flag and a red flag raise either to signal which competitor, they believe, won: the one with more flags raised in his or her favour is declared the winner. However discussions are still ongoing into the judging system, including whether to use a scoring system rather than the flag system.[16]
Due to the immense number of karate styles, each with its own katas, only katas from the styles recognized by the WKF (Gōjū-ryū,  Shitō-ryū, Shotokan and Wadō-ryū[17]) are allowed in the Olympics. The lack of representation of many karate styles in the kata competition generates much criticism from practitioners of these styles around the globe.