On the major Jewish holidays (Yom Kippur, Shemini Atzeret, and the last day of Pesach and Shavuot) there is a memorial service called Yizkor. In Hebrew, Yizkor means ‘may God remember.’ Traditionally, a yahrzeit candle is lit at sunset the night before each of these holidays to remember the deceased.
Originally, in the 12th century, the Yizkor service was said only on Yom Kippur to remember and honor those who were killed in pogroms and the Crusades. Over the years, Yizkor became a service to remember our own loved ones as well as the Jewish martyrs. About 400 years ago this service was added to the liturgy of Pesach, Shemini Atzeret, and Shavuot.
One usually says Yizkor on the first holiday after the death. In some congregations, those who do not have anyone for whom to say Yizkor leave the sanctuary. In other congregations, everyone stays throughout the service. Sometimes, additional prayers are said for Jewish martyrs and victims of the Holocaust.
The first word of the memorial prayer is Yizkor, and the prayers contain blank spaces where the names of deceased loved ones are recited. Kaddish is also chanted during the service.
Some people give tzedakah (charitable donations) around Yizkor to honor the memory of the deceased by perpetuating their values.