Fighting in ice hockey is an established aspect of the sport in North America, with a long history involving many levels of amateur and professional play and including some notable individual fights. Although a definite source of criticism, it is a considerable draw for the sport, and some fans attend games primarily to see fights. Fighting is usually performed by one or more enforcers, or "goons" players who are typically better at fighting than hockey on a given team and is governed by a complex system of unwritten rules that players, coaches, officials, and the media refer to as "the code". Some fights are spontaneous, while others are premeditated by the participants.[6] While officials tolerate fighting during hockey games, they impose a variety of penalties on players who engage in fights. Unique to North American professional team sports, the National Hockey League (NHL) and most minor professional leagues in North America do not eject players outright for fighting butmajor European and collegiate hockey leagues do. Therefore, the vast majority of fights occur in the NHL and other North American professional leagues.