There are quite a few sports in which you can engage in physical combat with another person. The most common and well-known of these is boxing, but there are others as well.
Mixed martial arts (MMA) is a popular combat sport that combines techniques from various other disciplines such as boxing, wrestling, kickboxing, and jiu-jitsu. MMA fighters typically use a wide variety of punches, kicks, knees, and elbow strikes to disable their opponents.
Kickboxing is another striking-based combat sport that has its origins in karate and Muay Thai. Like MMA, kickboxers use punches, kicks, knees, and elbows to defeat their opponents. However, unlike MMA fighters, they generally do not attempt takedowns or submission holds; the goal is simply to knock out the other fighter.
Wrestling is a different kind of combat sport in which competitors attempt to take each other down to the ground and pin their opponent's shoulders to the mat. Wrestling can be done with or without special equipment; freestyle wrestling (with no equipment) and Greco-Roman wrestling (wearing only a singlet) are two popular variations.
There are also several forms of armed combat sports such as fencing and kendo (Japanese swordsmanship). In these sports competitors face off against each other using blunted weapons such as swords or foils; the goal is not to injure your opponent but rather to score points by landing hits on specific target areas of their body.