Siyum HaShas (lit. "completion of the Six Orders [of the Talmud]") is the celebration of the completion of the Daf Yomi (daily Talmud folio) program, a seven-and-a-half-year cycle of learning the Oral Torah and its commentaries, in which each of the 2,711 pages of the Babylonian Talmud are covered in sequence. The first Daf Yomi cycle began on the first day of Rosh Hashanah 5684 (11 September 1923); the twelfth cycle concluded on 2 August 2012 and the next day began the thirteenth cycle, to be concluded on 4 January 2020. The Siyum HaShas marks both the end of the previous cycle and the beginning of the next, and is characterized by inspiring speeches and rousing singing and dancing.
For Jews for whom Torah study is a daily obligation, the publicity and excitement surrounding the Siyum HaShas has resulted in more participants, more Daf Yomi shiurim (classes), and more Siyum locations with each cycle. Since 1990, attendance at the main Siyum HaShas in America, organized by the Agudath Israel of America, has increased dramatically, necessitating the booking of larger arenas and stadiums. The 12th Siyum HaShas on 1 August 2012 took place in MetLife Stadium in New Jersey with a sellout crowd of over 90,000. Other celebrations that took place in the United States, Israel, Canada, Europe, and Australia attracted hundreds of thousands.
The novel idea of Jews in all parts of the world studying the same daf each day, with the goal of completing the entire Talmud, was put forth at the First World Congress of the World Agudath Israel in Vienna on 16 August 1923 by Rabbi Meir Shapiro, then Rav of Sanok, Poland, and future rosh yeshiva of Yeshivas Chachmei Lublin. In those years, only some of the 63 tractates of the Talmud were being studied regularly, such as Berachot, Shabbat, and Eruvin, which deal with practical laws, while others, such as Zevachim and Temurah, were hardly studied. Shapiro also viewed the program as a way to unify the Jewish people. His idea was greeted enthusiastically by the nearly 600 delegates at the Congress, including many Torah leaders from Europe and America, who accepted it as a universal obligation for all Jews. The first cycle of Daf Yomi commenced on the first day of Rosh Hashanah 5684 (11 September 1923).