Yom Kippur יוֹם כִּפּוּר, the Day of Atonement is the holiest day in Judaism. It occurs annually on the 10th of Tishrei, corresponding to a secular date in September or early October.
Primarily centered on atonement and repentance, the day’s main observances consist of full fasting and ascetic behavior accompanied by long prayer services in synagogue, as well as sin confessions.
Yom Kippur is the only day when fasting is permitted on Shabbat.
Alongside the related holiday of Rosh Hashanah, Yom Kippur is one of the two components of the “High Holy Days” of Judaism. It is also the last day of the Ten Days of Repentance.