Yom Kippur, the holiest day of the year in Judaism, begins this weekend.

The name Yom Kippur translates from Hebrew to English as the Day of Atonement. Jewish people may spend the day fasting, attending synagogue or observing the holiday in other ways. It follows Rosh Hashanah, the Jewish New Year.

Danielle Kranjec is the associate vice president of Jewish education at Hillel International. She explained what Rosh Hashanah and Yom Kippur represents in Judaism: “Spiritually, they say on Rosh Hashanah it is written, and on Yom Kippur it is sealed, the idea being that everything that's going to happen in the year to come, the stage is set during this time between Rosh Hashanah and Yom Kippur.”

For those unfamiliar with the holiday, here are some things to know.

What is Yom Kippur and how is it observed?  

Yom Kippur, or the Day of Atonement, is when Jews reflect on sins or wrongdoings from the previous year. Many Jews will attend services at synagogues or other congregations, reciting special prayers and singing special songs.  

One of the most common Yom Kippur traditions is to fast for 25 hours, not eating or drinking from the night Yom Kippur begins into the night it ends.

When is Yom Kippur? How long does it last?  

Yom Kippur begins at sundown on Sunday, Sept.24, 2023, and ends in the evening on Monday, Sept. 25, 2023. It lasts one day, while Rosh Hashanah lasts two days.

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What are common traditions during Yom Kippur?

Many Jewish families and communities will gather before Yom Kippur begins and after it ends to share festive meals, to prepare to fast and then to break their fasts together.  

Another important observance is the blowing of the shofar, or a curved ram’s horn. The shofar is sounded ceremonially to conclude Yom Kippur, Kranjec shared.  

“That is an important communal moment where the closing prayers of Yom Kippur are said together, and someone blows the ram's horn and everyone hears it together, and then the fast is broken together,” she said.  

How should you greet people during Yom Kippur?

"G’mar chatima tova” is the customary greeting on Yom Kippur. In English, it means “May you be sealed in the Book of Life.” 

According to Jewish tradition, one's fate is decided on Rosh Hashanah and sealed on Yom Kippur.

“In English, you might say to friends or colleagues ‘have a meaningful Yom Kippur,’ Kranjec shared. “Focusing on the meaning of the holiday and saying to people ‘have a meaningful fast if you're fasting,’ or you could even say, 'have a good Yom Kippur,' but happy is probably not the right adjective.” 

Marina Pitofsky contributed to this reporting