Shavuot is the Holiday that commemorates the reception of the Torah. It is also a harvest Holiday as you can understand from the other names of the Festival: Chag haKatzir (Festival of the Reaping) and Yom haBikkurim (Day of the firsts (fruits etc.)). It is customary to dress up in white, eat dairy products, exchange baskets of fruit, vegetables and dairy (Tenne) and have children wear flower wreaths. I have asked why there is this strong connection with white and dairy and obtained various answers over the years. One is that the Israelites were white as children (innocent, naive, ignorant), when they got the Torah. Another is that the laws for kashrut were not yet known and so they ate dairy. And yet another is that in order to be ready to obtain the Law, the Jews must wash up and become white.
Well, I am no scholar and here is not the place I want to criticize these explanations. All I want to say is that, more than with any other Jewish Holiday, the liturgic meaning of the chag (Reception of the Law), is overshadowed by the additional meaning, by the look of things. This additional meaning, totally dominates the holiday and makes it for the secular newbie that I am, an exclusive harvest festival. It is all about the first fruits and grains and milk that have been reaped. It makes it more likely than with other religious festivals, that this festival was mapped onto an older, rural, maybe even pagan festival.
The amazing thing is, that these Jews that are more urban than ever, still live the earliest roots of the chag in a stronger sense than the newer ones.