Boxing as a combat sport has been an established Olympic sport since 688 BC (Ancient Greece). The popular sport resurfaced in England in the early 16th century, and it has quite the history and controversy that most other sports do not have. Not only because it supports the expression of strength and power through fighting, but also because throughout the years, boxing has had little to no rules, has been connected to gambling, questionable judges and referees, and the "underground" world. Of course, not leaving out the fact that in its beginnings, fights were bare-knuckle fights, which was later pronounced as assault because of the damage that it could cause. It was only by 1867 that the Marquess of Queensberry rules were drafted by John Chambers, rules still in use in the modern era.
From the early 1900s, boxing started to develop and evolve into a more sophisticated, technical, and controlled sport. Boxing takes place on a boxing ring, and it is a form of sport in which two people compete by throwing punches at each other in predetermined time intervals (rounds), normally held between 1-3 minutes and can last for as long as twelve rounds or as little as one. The match is controlled, overseen, and judged by a referee on the ring, and by up to three judges ringside scoring each of the fighters based on measures such as punches, defense, technique, hugging, and other characteristics. A bout or fight is over when either all the rounds have been fought and the judges give the final score, or when a fighter knocks out the other fighter. In the latter, the referee will count to ten, which is the amount of time that the knocked-down fighter must get up and return to their corner or stay down and the fight is declared over. A draw, unanimous and split decisions are possible when judges put out their scores. Even though this scoring system has been tagged as subjective and controversial at times, it has been established that way since the year 1867 and has barely changed.
Modern boxing has two main categories: Amateur and Professional boxing for both female and male fighters. Amateur boxing is mainly found at the collegiate level. It has become an important event of the Olympic Games (in the modern Olympics, it became an Olympic sport in 1908), the Commonwealth Games, as well as other international championships. It also has its own World Championships. Amateur boxing is almost always limited to three or four rounds, and the scoring system differs in a way that blows are counted as the number of clean blows landed, regardless of how strong the punch may be. Also, besides the gloves, amateur boxers wear protective headgear, which reduces injuries to the head. The amateur level is where boxers start their career and qualify enough to move on to Professional boxing. Professional boxing is longer as it ranges from ten to twelve rounds, headgear is not allowed, and it is more common for boxers to get harder blows and more serious injuries because the referee is more permissive with the punches and flow of the fight.
The Association Internationale de Boxe Amateur (AIBA) was established in 1946 and sanctions amateur boxing matches but has also been trying to develop its own semi-professional version of boxing. Through the World Series of Boxing (WSB) it allows boxers to compete professionally while maintaining amateur status and Olympic eligibility. AIBA is now called the International Boxing Association (IBA).