Here's
a link to Wikipedia's entry on the meaning of today's Jewish holiday, which celebrates a historic victory over an ancient Persian plan to exterminate the Jews, the triumph of Mordechai and Queen Esther over Haman:
The events leading up to Purim were recorded in the Megillat Esther (the Book of Esther), which became the last of the 24 books of the Tanakh to be canonized by the Great Assembly. The Book of Esther records a series of seemingly unrelated events which took place over a nine-year period during the reign of King Ahasuerus. These events, when seen as a whole, reveal that the "coincidences" are really evidence of Divine intervention operating behind the scenes. This interpretation is developed and explained by Talmudic and other major commentaries on the Megillah.
The holiday of Purim has been held in high esteem by Judaism at all times; some have held that when all the prophetical and hagiographical works are forgotten, the Book of Esther will still be remembered, and, accordingly, the Feast of Purim will continue to be observed (Jerusalem Talmud, Megillah 1/5a; Maimonides, Yad, Megillah).
Like Chanukkah, Purim's status as a holiday is on a lesser level than those days ordained holy by the Torah. Accordingly, business transactions and even manual labor are allowed on Purim, though in certain places restrictions have been imposed on work (Shulkhan Arukh, Orach Chayim, 696). A special prayer ("Al ha-Nissim"—"For the Miracles") is inserted into the Shemoneh Esrei during evening, morning and afternoon prayers, as well as is included in the Grace after Meals.
The four main mitzvot of the day are:
*listening to the public reading, usually in synagogue, of the Book of Esther in the evening and again in the following morning
*sending food gifts to friends
*giving charity to the poor
*eating a festival meal
Here's
a link to Purim Gateway, and another
link to Mordechai Housman's English translation of the Book of Esther.
