Yom Kippur, one of the most important holidays in the Jewish faith, begins Tuesday, at sunset and will continue through nightfall Wednesday.

A major holiday sometimes referred to as the “Sabbath of Sabbaths,” Yom Kippur is observed as a Day of Atonement in the Jewish religion. It falls in the month of Tishrei on the Jewish calendar and is marked by Jews around the world.

Here are 14 things to know.

  1. Yom Kippur falls in September or October in the Gregorian Calendar
  2. The day is the culmination of the Days of Awe, which is the period of repentance that begins with the Jewish New Year, Rosh Hashanah.
  3. On Yom Kippur, Jews ask for forgiveness and pardon for sins committed in the previous year and resolve to do better in the year ahead.
  4. Fasting is commonly practiced from sundown to sundown.
  5. Some Jews also follow restrictions on cosmetics, washing and bathing.
  6. Sexual abstinence is sometimes practiced as well.
  7. During biblical times, Yom Kippur was the only day that a high priest was allowed to enter the inner sanctum of the Holy Temple of Jerusalem, known as the Holy of Holies.
  8. The blowing of a ram’s horn, or the shofar, is part of the temple service.
  9. Many Jews observe Yom Kippur by not working and attending services.
  10. Traditional Yom Kippur garb is white, to represent purity.
  11. Observant Jews avoid wearing leather on the holiday, since that results from the taking of a life.
  12. Five prayer services are led on Yom Kippur, and continue over through the next day.
  13. Families typically eat a large, pre-Yom Kippur meal before the sun sets and the fast begins.
  14. Another large meal takes place to break the fast the following day, and many indulge in foods and sweets like noodle pudding and blintzes.