Sparring is a form of online role-play that deals with combat between two or more characters, usually conducted on play-by-post media. Two or more players take turns in writing a joint-narrative battle, each one attempting to defeat his or her rival. The battle ends when one participant acknowledges defeat or one is judged the victor by an unbiased arbiter after a review of all related posts. In the context of Internet-based role-play, sparring retains its traditional meaning of play or practice combat, but is limited to written interaction. It is different from role-play in that sparring usually contributes little, if nothing, to a story or character development and participants are subject only to the rules of an agreed on role-play fighting system.