1. It is customary to give money to charity on the eve of Purim as commemoration of the yearly Half-Shekel that was given to the Temple. Some have the custom of giving one coin of half a Shekel in today’s currency], while others give three coins of half a Shekel each preferably in the form of three separate coins]. Still others have the custom of giving the value of half a silver Shekel that in circulation during the Temple era, which is 9.6 grams of pure silver nowadays, its value is around 30 Israeli New Shekels] (Shulchan Aruch, Mishnah Berurah and Kaf HaChaim 694).
2. Some authorities say that this obligation only applies to men of the age of thirteen, while others maintain that it is from the age of twenty. Some have the custom to give for women and children as well (ibid.).
