In the biblical tradition, the holiday of Shavuot marks the end of the grain harvest and the bringing of the first fruits. Shavuot comes 50 days after Passover and those 50 days, which we mark even today with the ritual of counting the Omer (sheaves), were a time of great trepidation in anticipation of the quality of the harvest.
Following the destruction of the Temple in Jerusalem in 70 A.D., the focus of the holiday appears to have shifted to a celebration of the receiving of the Torah.
This remains the identity of the holiday to this day.
We continue to ritually count those 50 days, now in anticipation of receiving the gift of the Torah. Echoing the holiday's agricultural roots, synagogues, and even the Torah itself, are often decorated in fresh greenery as part of the celebration.
This celebration is uniquely suited to the university environment — its central observance is all-night study of the Torah and other Jewish texts.
It is tradition to eat dairy foods on Shavuot, because of the notion that the laws of keeping kosher were not given until the Torah was received and because the words of the Torah should be sweet in our mouths.