April 19th is Yom HaShoah. As with most Jewish holidays, it begins at sundown the evening before.

Yom HaShoah is a new holiday, designated by the Knesset (Israeli Parliament) in 1953, commemorating the victims of the Holocaust. The full name is Yom HaShoah veHagevurah, the Day of Remembrance of the Holocaust and the Heroism. It occurs each year on the 27th of Nisan, except when adjacent to Shabbat, when it moves one day.

In Israel, a ceremony is held at Yad Vashem at sundown. Flags are flown at half mast. The entire day is very solemn. In the morning, sirens are sounded throughout Israel for two minutes when the entire country stops to pay silent tribute. Even on highways, drivers stop their cars and wait in silence. Public entertainment venues are closed by law.

Many Orthodox do not commemorate this date, instead using the 10th of Tevet or Tisha b’Av for remembrance.

Outside of Israel, commemorations range from synagogue services to community vigils and educational programs. Rituals are still being created and vary widely but usually include the lighting of a Yahrzeit (memorial) candle and recitation of the Mourner’s Kaddish.

In 1980, the US Congress designated an eight day period of The Days of Remembrance of the Victims of the Holocaust (DRVH), beginning the Sunday before Yom HaShoah and continuing until the following Sunday. The US Holocaust Memorial Museum designates a theme for each year’s programs. For 2012, the theme is Choosing to Act: Stories of Rescue, and DRVH is from April 15-22.

In 2005, the United Nations also designated an International Holocaust Remembrance Day for the 27th of January.

Most of this information and more can be found at some of the following web sites: Wikipedia, Jewish Virtual Library, and the US Holocaust Memorial Museum.

Friday night begins the holiday of Passover, or Pesach in Hebrew. Passover lasts for eight days, but like most Jewish holidays, it begin at sundown. No work is permitted on the first two days and the last two days of the holiday.

Passover commemorates the Exodus of Jews from Egypt. The first two nights involve the Seder, a family meal filled with rituals and the reading of the Haggadah. The Haggadah tells the story of the Exodus from Egypt and explains some of the practices and symbols of the holiday.

As with some other holidays, the observances in Israel differ from the rest of the world. In Israel, Passover only lasts for seven days, the Seder is only on the first night, and work is not permitted on the first and last days.

A significant observance of Passover involves avoiding Chametz, which is any leavened food, commemorating when the Jews left Egypt in a hurry and did not have time to let their bread rise. Chametz includes anything made from the five major grains of wheat, rye, barley, oat, and spelt. Ashkenazi Jews will also avoid rice, corn, peanuts, and legumes. Not only can Chametz not be eaten, it must not be owned or even fed to pets or other animals. Before Passover, Jews will dispose of their Chametz by cleaning the entire house of it. A formal search for Chametz will occur before the first Seder where any remaining Chametz is burned. One such tradition is to place pieces of bread to be found, which are then swept up with a feather, to ceremoniously finish cleaning the house.

Depending on their level of observance, some Jews will cover all kitchen surfaces and kasher all of their kitchen items, or have an entirely separate set of dishes, utensils, pots, and pans just for the holiday.

Since bread is not allowed, Jews will each Matzah, unleavened bread, made simply from flour and water and cooked very quickly.

Some of the information in this article was found at Judaism 101, where more details about the holiday can be found. For those interested, About.com has a list of Haggadahs (Haggadot in Hebrew) that are online and can be downloaded free.