Tu BiShvat or the "New Year of the Trees" is Jewish Arbor Day. The holiday is observed on the 15th (tu) of the Hebrew month of Shvat.
Purim is a joyous holiday that affirms and celebrates Jewish survival and continuity throughout history. The main communal celebration involves a public reading—usually in the synagogue—of the Book of Esther (M'gillat Esther), which tells the story of the holiday: Under the rule of King Ahashverosh, Haman, the king's adviser, plots to exterminate all of the Jews of Persia. His plan is foiled by Queen Esther and her cousin Mordechai, who ultimately save the Jews of Persia from destruction. The reading of the m'gillah typically is a rowdy affair, punctuated by booing and noise-making when Haman's name is read aloud.
Passover (Pesach in Hebrew) is a major Jewish spring festival, celebrating freedom and family as we remember the Exodus from Egypt more than 3,000 years ago.
Yom HaShoah, also known as Holocaust Remembrance Day, occurs on the 27th of the Hebrew month of Nisan.
Yom HaZikaron (Israel Memorial Day) and Yom HaAtzmaut (Independence Day) are observed in Israel as national holidays.