Boxing is a combat sport. In both amateur and professional versions, the fighters wear padded gloves, attacking only with the front of the fist. In professional boxing each round usually lasts for three minutes and there may be 4-12 rounds in a bout. The winner is the one who knocks out his opponent or is judged to be the winner at the end of the bout or if the referee or ring side doctor stops the fight. Boxing is also called Pugilism and prizefighting.