Although the Torah makes frequent mention of the obligation of Shabbat observance, its importance and the severity of its violation[1], the Mishna in Masekhet Chagiga (10a) declares, "The laws of Shabbat are like mountains suspended by a hair." These halakhot, with which we will deal in this series, entail fundamental principles described by the Mishna as "mountains," all of which are "suspended by a hair," as the written Torah offers very little information concerning the halakhic details of Shabbat. It only alludes to them in various places, such that they can be determined only through Chazal's derashot (extrapolations from the text).