 Etymologically, the term, "hasid" is a title used for various pious individuals and by various Jewish groups since Biblical times, and an earlier movement, the Hasidei Ashkenaz of medieval Germany was also called by this name.Today, the terms hasidut and hasid generally connote Hasidic philosophy and the followers of the Hasidic movement.Hasidic philosophy begins with the teachings of Yisroel ben Eliezer known as the Baal Shem Tov and his successors (most notably Dov Ber the Maggid of Mezeritch and his students).