Halakha (Jewish law), especially the Talmud tractate Shabbat, identifies thirty-nine categories of activity prohibited on Shabbat (Hebrew: ל״ט אבות מלאכות, lamed tet avot melakhot‎), and clarifies many questions surrounding the application of the biblical prohibitions. Many of these activities are also prohibited on the Jewish holidays listed in the Torah, although there are significant exceptions permitting carrying and preparing food under specific circumstances. There are often disagreements between Orthodox Jews and Conservative Jews or other non-Orthodox Jews as to the practical observance...