Shulchan Aruch שולחן ערוך

Rabbi Yosef Karo, a refugee from Spain living in Tzfat, first wrote the Beit Yosef, an immense survey of sources following the order of the Tur. He then compressed the result into bare rulings, «so that a young man may repeat them by heart», and called it Shulchan Aruch — a set table: everything ready, take and eat.

In disputes he followed the majority of three authorities — Rif, Rambam and Rosh — which meant, in the main, Sephardi practice. The Ashkenazi world might not have accepted it; but Rabbi Moshe Isserles of Krakow wrote glosses called the Mappah, a cloth for that table, noting where Ashkenazi custom differs.

The two have been printed together ever since, and their combination made the work universal: one code for two traditions. A library of commentary grew around it, and every halachic question still begins there.