The days between Passover and Shavuot are marked by pain; twenty-four thousand of Rabbi Akiva’s students died therein. Consequently, it is customary to observe mourning practices during this period - weddings, haircuts, and dancing are all forbidden.
Each year we merit preparing ourselves once again for the Festival of the Giving of the Torah. As a result, we become worthy on Shavuot of absorbing even more of the Torah's light.