Why do we send Mishloach Manos on Purim?
Answer:
The Megillah mentions the concept of sending mishloach manos “each man to his fellow,” and the Gemara (and later authorities) understands this to be one of the rabbinic enactments of the Purim day.
The idea of the mitzvah is to heighten the sense of unity and rejoicing that is appropriate for Purim, the day on which the Jewish People were saved from destruction.
Also, the day of Purim is considered to be a day on which the Torah is accepted anew; just as the accepance of the Torah required a special unity of the people, so Purim is a time for unity and comradeship, which is achieved by mishloach manos.
Best wishes.
