The Jewish High Holidays (or High Holy Days), the 10 days starting with Rosh Hashanah and ending with Yom Kippur, are known as the Days of Awe or the Days of Repentance. This is an introspective time, when Jews consider the sins of the previous year and repent before Yom Kippur.

This year, Rosh Hashanah, the Jewish New Year, starts on the evening of Sept. 18, and is observed by some for two days. Yom Kippur, the Day of Atonement, begins on the evening of Sept. 27. Each lasts 24 hours, from sunset to sunset.

Rosh Hashanah is the beginning of the new year on the Hebrew calendar. While it is a festive holiday (one common celebration is a treat of apples dipped in honey "for a sweet New Year"), no work is permitted on Rosh Hashanah. Observant Jews spend the day at synagogue, attending religious services and contemplating the past and upcoming year.

Tradition holds that on Rosh Hashanah, God makes inscriptions in the Book of Life for the coming year. On Yom Kippur, those decisions are sealed.

Yom Kippur is the most solemn -- and most holy -- day on the calendar. It is the Day of Atonement, when Jews ask for God's forgiveness for sins against the Almighty. An important precept in Judaism is that people must ask forgiveness from those that they have wronged, and this is to happen in the Days of Repentance.

Also on Yom Kippur, those who are physically able are called upon to fast for 24 hours, neither eating nor drinking. Many Jews who do not observe other Jewish customs will refrain from work, fast and attend services on this day.

The holidays are tied together symbolically by the blowing of the shofar, a ram's horn that was traditionally used to call Jews to prayer.

Additional Resource:

• More on the High Holidays