Yahrzeit 

Yahrzeit is a commemoration of the anniversary of the death of a relative.  It includes reciting the Mourner's Kaddish and lighting a Yahrzeit candle, a special memorial candle that burns for 24 hours.  Only one Yahrzeit candle needs to be lit per household. (Today, some people use an electric bulb instead of a candle for safety reasons.)  The Yahzeit candle should be lit after dark on the evening before the anniversary of the death and should burn for a full 24 hours. Many people visit the graves of the deceased on the Yahrzeit. Some people observe Yahrzeit by fasting.

The name of the deceased relative is read at Shabbat services on the Shabbat anniversary nearest their death. One may follow the Hebrew or English calendar in reckoning the date of the Yahrzeit. Inform the Temple office of your preference. A Yahrzeit notification letter is sent from the Temple. Attendance at this service is a sacred mitzvah.

Yizkor  

Yizkor is recited by those who have lost an immediate family member.  It is recited four times a year: on Yom Kippur, the last days of Pesach and Sukkot, and on Shavuot.