What is Purim in a nutshell? 

Purim is a Jewish holiday that commemorates the salvation of the Jewish people from the plot of Haman, a Persian official who sought to exterminate the Jews in the ancient Persian Empire. The story of Purim is told in the Biblical Book of Esther, and the holiday is typically celebrated on the 14th and 15th of Adar, the twelfth month of the Jewish calendar.

During Purim, Jews read the Book of Esther, exchange gifts of food and drink (known as mishloach manot), give charity to the poor, and hold festive meals. The holiday is also marked by the wearing of costumes and masks, and the making of noise with noisemakers (known as groggers) during the reading of the Book of Esther. Overall, Purim is a celebration of the triumph of good over evil and the enduring strength of the Jewish people.