This document provides an introduction to the Talmudic tractate of Shabbat. It summarizes that Shabbat discusses the laws and observances related to the Sabbath, including what constitutes prohibited labor. It explains the origins of these laws in the Torah and how rabbinic oral tradition expanded the prohibited acts of labor to 39 categories. The introduction also describes how the laws were strengthened over time, such as restricting movement and carrying items, to prevent assimilation with non-Jewish neighbors and encourage distinct Jewish communal identity and observance of the Sabbath.