Jewish

Yom Kippur is often considered the holiest day of the year for Jews, and the day is dedicated to atonement, repentance, and forgiveness.

Date details: Begins at sundown on the first evening listed and ends at nightfall of the second date listed.

General practices: Prayer in synagogue both at night and all day the following day. During Yom Kippur, Jews fast from before sundown until  nightfall the following day.  A Yahrzeit memorial calendar is lit prior to the beginning of the holiday, and burns through the duration.  Refraining from certain activities that are defined as work, including (depending on the level of observance): the use of electricity and electrical devices, use of cell phones and computers, riding in a car or public transportation, and writing.