Yom Kippur is the Day of Atonement. It is the most solemn and holy day of the Jewish calendar. Yom Kippur is observed on the 10th day of the Hebrew month of Tishrei. (The Hebrew calendar, which is based on a combination of a lunar and solar calendar, is different from the Gregorian calendar. Thus, the date of Yom Kippur, while fixed on one calendar, appears to move around on the other.) It falls ten days after Rosh HaShanah. Together, Yom Kippur and Rosh HaShanah constitute the “High Holy Days” of the Jewish calendar.
Yom Kippur is a day spent in personal and communal repentance and penitence. Jews spend the day together in synagogue, offering a set ritual of prayers asking for forgiveness, not only for oneself, but in the plural.
No work is performed on the day of Yom Kippur. In addition, there are five main restrictions placed on Jewish adults for the observance of Yom Kippur. The most well-known is the complete 25-hour fast that begins on the eve of the holiday and continues until nightfall. One refrains from eating and drinking, including water, for the entire fast. Other restrictions are: no bathing or washing, no anointing one’s body (with lotions or cosmetics), no wearing of leather shoes, and no engaging in sexual activity.
It is also customary to wear white, a symbol of purity. Often, worshipers will wear a kittel, a white robe in which Jews are buried.