Wulin (Simplified Chinese: 武林) is a term referring to a subset within Jiang Hu (江湖). It has been variously translated as "the World of Martial Arts", "the Pugilistic Fraternity" and "the Circle of Warriors". The standard of morality within Wulin is less vigorous than that in Jiang Hu. Law and order is maintained by the alliance of Wulin or Wulin mengzhu who is sometimes be nominated and voted for this role. This alliance leader is an arbiter, who presides and adjudicates over inequities and disputes. He is a chief justice of the affairs of Jiang Hu.
Inhabitants of Wulin are clearly distinguished from those within Jiang Hu, in that they all know or grasp some form of martial arts. It's a counterculture of martial artists. And the way to differentiate the good from the bad within Wulin is the code of Xia (俠), those who adhere to it are good, those who do not are bad. It is common to split Wulin into black and white ways, denoting the criminous and virtuous. Murderers, rapist, robbers, pirates and those less scrupulous belong to the black way would live in Wulin with a bad reputation, until someone would seek justice upon them. The virtuous white way adherents are commonly represented by the major schools including Shaolin, Wudang, Emei to name a few, who are the benchmark good guys of Wulin.