Purim is celebrated on the 14th of Adar. On the evening of the 13th of Adar, and on the morning of the 14th, the Megillat Esther (scroll of Esther) is read.
The book of Esther tells of the plan of Haman, a minister at the time of King Xerxes in 485 - 465 BC, who wanted to destroy the Persian Jews. Haman chose the date of the annihilation with one lot (in Hebrew: "Pur", several lots - in Hebrew: "Purim"), hence the festival name of Purim. Only through the Jewess Esther (the wife of the king) was this project stopped and Haman received his just rewards.
It is customary to dress up in costrume for Purim and to exchange gifts of food baskets.
Only while supplies last!