This year the Jewish Holiday of Purim is being held from Sunset on 7th March until Nightfall on the 8th March 2012. It commemorates the deliverance of the Jewish people in the ancient Persian Empire from destruction in the wake of a plot by Haman, a story recorded in the Biblical Book of Esther (Megillat Esther). Purim is celebrated annually according to the Hebrew calendar on the 14th day of the Hebrew month of Adar (Adar II in leap years), the day following the victory of the Jews over their enemies.
Purim begins at sundown. In cities that were protected by a surrounding wall at the time of Joshua, Purim is celebrated on the 15th of the month; Everywhere else, Purim is on the 14th, while the 15th is known as Shushan Purim. Due to Jerusalem’s importance, it celebrates Purim on the 15th despite it not having been surrounded by a wall since the time of Joshua. This is to prevent less-holy cities having an advantage over Jerusalem.
Purim is characterized by public recitation of the Scroll of Esther (keriat ha-megillah), additions to the prayers and the grace after meals (al hannisim), giving mutual gifts of food and drink (mishloach manot), giving charity to the poor (mattanot la-evyonim), and a celebratory meal (se’udat Purim); other customs include drinking wine, wearing of masks and costumes, and public celebration. According to the Book of Esther, Haman, royal vizier to King Ahasuerus planned to kill the Jews, but his plans were foiled by Mordecai and Queen Esther. The day of deliverance became a day of feasting and rejoicing.