Rosh Hashanah is the Jewish New Year and takes place on September 14, 2015. Translated it means "head of the year" and it is the first of the High Holy Days which usually occur in the early autumn of the Northern Hemisphere. Rosh Hashanah is a two day celebration which begins on the first day of Tishrei, the first month of the Jewish calendar. The day is believed to be the anniversary of the creation of Adam and Eve, and their first actions toward the realization of mankind's role in God's world.
Rosh Hashanah customs include sounding the shofar and eating symbolic foods such as apples dipped in honey. The common greeting on Rosh Hashanah is "Shanah Tovah." In Jewish liturgy, Rosh Hashanah leads to Yom Kippur, which is described as "the day of judgment" and "the day of remembrance”. Rosh Hashanah occurs 163 days after the first day of Passover (Pesach). The earliest date on which Rosh Hashanah can fall is September 5, the latest date that Rosh Hashanah can occur relative to the Gregorian dates is October 5.
The High Holidays or High Holy Days, in Judaism, more properly known as the Yamim Noraim may mean strictly, the holidays of Rosh Hashanah ("Jewish New Year") and Yom Kippur ("Day of Atonement") or by extension, the period of ten days including those holidays, known also as the Ten Days of Repentance (Aseret Yemei Teshuvah). By a further extension, the entire 40-day penitential period in the Jewish year from Rosh Chodesh Elul to Yom Kippur can be meant. (With material from: Wikipedia)