NEW YORK (CBSNewYork) — Yom Kippur, the holiest day of the Jewish year, begins at sundown Friday.

Yom Kippur is the day of atonement. It marks the end of a 10-day period of reflection and repentance beginning after Rosh Hashanah, the Jewish new year.

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Observant Jews will fast for 25 hours.

Yom Kippur ends at sundown Saturday with a blast from the shofar, an ancient instrument made of a ram’s horn.

Earlier in the day, CBS2’s Cindy Hsu took a look at the holiday through the eyes of children.

Shormi Uddin was teaching kids at the Children’s Museum of Manhattan to make charity boxes for Yom Kippur.

“By making these boxes, kids get to learn more about the Jewish religion and maybe even more about charity,” she said.

Noa Abehassera, 9, described Yom Kippur as “I know that it’s a day where we say sorry to all the people we did bad things to.”

Rabbi Peter Rubinstein with the 92nd Street Y said it’s a peaceful day of rest and prayer where many attend synagogue, and it’s a time to put things behind you and start fresh.

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“It’s an opportunity for people to reflect on their lives and to ask forgiveness of those they know, even though they may not have thought they wronged them,” he said.

It’s also a day to fast, giving up food and drink from sundown Friday until sundown Saturday. Children aren’t expected to fast until they’re 12 or 13.

It’s a tradition both Shoshana and Miriam will take part in this year.

“You don’t eat or drink for 25 hours, which makes it really hard, but also reminds you all the time what you’re doing,” Miriam said.

“It helps you concentrate more on your mistakes in your past, so you can focus more on what you’ve done and to have God forgive you,” Shoshana added.

Yom Kippur is a solemn holiday to slow down and put things in perspective.

“This year, I definitely want to maintain a really close relationship with my family and friends and work hard to make time for everything,” 15-year-old Jacob Brooks said.

After Yom Kippur, some families will start preparing for Sukkot, which starts next Wednesday and will lead to the end of the Jewish holidays.

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Some other traditions observed are not wearing leather shoes, lotions or perfumes. Also not bathing or washing to move away from the comforts of life and really focus on repenting.