Shavuot or Shavuos is known as the feast of weeks as we celebrate the completion of the seven weeks of counting the Omer and is between Pesach and Shavuos
Shavuos begins at sunset on Shabbat the 5th of Sivan until nightfall the 7th of Sivan.
Every year on Shavuos we renew our acceptance of HaShem's gift, and HaShem will give us the Torah as as a re- gift.
The Torah been given to the Jews on mount Sinai to Moshe Rabbineu by HaShem on Shavuos over 3000 years ago. The giving of the Torah was one of the most spiritual events, which touches the essence of our being, our Neshama, forever.
Shavuos means oath, for on this day HaShem swore his devotion to the Jewish people and in return we promised to be forever loyal to Him.
How do we celebrate Shavuos
Women and Girls light the chandles, this is in both days as we enter the holiday, on the first night of Shavuos we study the Torah all night, or at least as long as possible.
On the first day the whole family goes to Shul to hear the reading of the Ten Commandments. On the second day we recite the Yizkor in Shul, Yizkor means "remember" and with this prayer we ask HaShem to remember the Souls of our family and friends who have passed away.
When we recite Yizkor, renew de connection between our family and friends and ourselves, this will bring more goodness to their souls in order to elevate them. Yizkor is also about to give to charity in honor of the deceased, we perform a positive deed in this world as they can no longer do this, so we do it for them instead.
Who recite the Yizkor is everone who last their parents or one of them, for everyone who still have two parents alive has to leave Shul during the service. For one's parent, one may recite for any Jew who has passed away, this could also be family or friends.