“Shas” – the Hebrew abbreviation (“Shin” – “Samech”) for “Shishah Sedarim,” or the Six “Orders” of the Mishna, compiled by Rabbi Yehudah HaNasi, Rabbi Judah the Prince, otherwise known as “Rebbe”
The names and basic contents of the “Orders” are:
“Zeraim” – literally, “Seeds;” dealing primarily with Laws of an agricultural nature, particularly those that apply only in “Eretz Yisrael,” the Land of Israel
“Moed” – literally, “Festival;” dealing primarily with the Laws of Shabbatand the Holidays
“Nashim” – literally, “Women;” dealing primarily with Laws of Marriage and Divorce
“Nezikin” – literally, “Damages;” dealing primarily with Laws of civil and criminal nature, corporal and capital punishment; principles of Jewish Ethics
“Kodshim” – literally, “Holy Things;” dealing primarily with Laws regarding the various sacrifices offered in the Temple, and Kashrut, Jewish dietary laws
“Taharot” – literally, “Purity;” dealing primarily with Laws of ritual purity and impurity
Both the Babylonian Talmud (“Talmud Bavi”) and the Jerusalem Talmud (“Talmud Yerushalmi”) contain Gemara text on most of the various tractates, or volumes, within the six “Orders.” Therefore, the term “Shas” also refers secondarily to the Six “Orders” of the Talmud.