Cult is a lay term for a group perceived as requiring unwavering devotion to a set of beliefs and practices which are considered deviant outside the norms of society. Such groups are typically founded or led by a charismatic and self-appointed leader who tightly controls its members. It is in some contexts a pejorative term, also used for new religious movements and other social groups which are defined by their unusual religious, spiritual, or philosophical beliefs and rituals, or their common interest in a particular person, object, or goal. This sense of the term is weakly defined – having divergent definitions both in popular culture and academia – and has also been an ongoing source of contention among scholars across several fields of study.: 348–356  An older sense of the word, which is not pejorative, involves a set of religious devotional practices that is conventional within its culture, is related to a particular figure, and is frequently associated with a particular place. References to the imperial cult of ancient Rome, for example, use the word in this sense. A derived sense of "excessive devotion" arose in the 19th century. Beginning in the 1930s, new religious movements perceived as cults became an object of sociological study within the context of the study of religious behavior. Since the 1940s, the Christian countercult movement has opposed some sects and new religious movements, labeling them "cults" because of their unorthodox beliefs. Since the 1970s, the secular anti-cult movement has opposed certain groups and, as a reaction to acts of violence, frequently charged those cults with practicing brainwashing. Groups labelled "cults" are found around the world and range in size from local groups with a few members to international organizations with millions. Source: Wikipedia (en)