As the 2nd of the trilogy of biblical festivals (Passover, Shavuot and Sukkot), Shavuot commemorates one of the most pivotal events in world history: The giving of the Torah at Mount Sinai.
A highlight of Shavuot is the traditional reading of the Ten Commandments. It is also customary to eat dairy foods on Shavuot, as well as to stay up studying Torah on the first night of the holiday.