Yom Kippur (the Day of Atonement) is one of two Jewish High Holy Days. The first High Holy Day is Rosh Hashanah (the Jewish New Year). Yom Kippur falls ten days after Rosh Hashanah on the 10th of Tishrei–the Hebrew month that correlates with September-October on the secular calendar. The purpose of Yom Kippur is to bring about reconciliation between people and between individuals and God. According to Jewish tradition, it is also the day when God decides the fate of each human being.
Although Yom Kippur is an intense, solemn holiday, it is nevertheless viewed as a happy day, since if one has properly observed this holiday, by the end of Yom Kippur they will have made lasting peace with others and with God.