 Most often a "gadol" functions as a "rosh yeshiva" (the head of a yeshiva Talmudical school), and can be a Hasidic Rebbe.A "gadol" is quite often also a "posek" (a decisor of Halakha - Jewish law) and may be the author of rabbinic literature and responsa.Adherents of Haredi Judaism often presume that a "gadol" has some degree of "ruach hakodesh" ("divine spirit"); the "gadol"'s teachings and statements therefore become the crux of Daas Torah.