Lag B'omer
Lag B'omer (Sephardi Jews), also known as Lag BaOmer or Lag LaOmer is a Jewish holiday celebrated on the 18th day of the Hebrew month of Iyar, which is also the 33rd day of the Counting of the Omer.
It is a celebration of the great light that Bar Yochai brought into the world. Bar Yochai was a great teacher of Torah and is beleived to be tha author of the Zohar, a great book on Judaism.
While the Counting of the Omer is a semi-mourning period, all restrictions of mourning are lifted on Lag B'omer (the 33rd day of the Omer). Many inside and outside Israel celebrate by gathering around bonfires.