Haredi Judaism (or Haredism) is a label used to describe the most religiously orthodox variants of Judaism. Within Orthodox Judaism, it is typically contrasted to Centrist and Modern Orthodox Judaism. It consists of three distinctive subgroups:
- Lithuanian Judaism, named such due to the Lithuanian background of most of its adherents and leaders, also commonly referred to by its Yiddish name: Litvish Judaism;
- Hasidic Judaism, consisting of numerous subgroups;
- Sephardic Haredi Judaism, which is ideologically loosely affiliated with Lithuanian Judaism.
The term "Haredi" comes from a Hebrew verb meaning "to tremble."
Haredi Judaism is often referred to as 'ultra-Orthodox' Judaism; however, some adherents do not appreciate this description, since in their view, they are merely religious Jews who are following God's commandments, and not extremists. Another often-used characterization is 'black-hatters,' referring to the fact that most male Haredi Jews wear black hats.