• Why one eats matzo (to remember their ancestors, who fled Egypt in a hurry and did not have time to let their bread rise before the journey).
• Why one eats bitter herbs (a reminder for the bitterness of slavery).
• Why one dips parsley in salt water (a symbol for the tears shed by slaves) and bitter herbs in charoseth, a sweet fruit paste (the texture evokes the mortar slaves used when making bricks).
• Why one leans on a pillow or reclines during the meal (to symbolize the comforts of freedom).
Passover lasts eight days and begins with two nights of Seders. Traditions vary, but most Jews eschew "the five species of grains" — wheat, rye, oats, barley and spelt, all of which contain gluten. The exception is matzo, which is made from wheat, but has not been allowed to ferment. Matzo must be baked within 18 minutes of the flour being combined with water.
Passover favorites include brisket, roast lamb and a variety of side dishes, such as potato kugel, tzimmes (sweet potatoes and carrots) and assorted casseroles bound together with eggs and matzo meal.
For dessert, expect macaroons, fruit compote, candy and cakes and tortes made with ground nuts or other kosher-for-Passover flours. Beer and most liquor is not allowed, but wine generally flows freely throughout the Seder.
The Seder consists of 15 rituals, most of which occur before the meal is served. They include lighting candles, blessing wine, washing hands, breaking the matzo, dipping vegetables and telling the story of the exodus from Egypt.
Usually, one of the hosts serves as the leader, but guests take turns reading sections from the Haggadah. Interspersed are various traditional songs. Many Seders also feature contemporary readings on the themes of slavery and liberation.
• Don't touch the food on the Seder plate, a large dish that holds a shank bone, parsley, bitter herbs, a hard-boiled egg, charoseth and matzo.
• If you bring wine or prepared food, make sure it is labeled "Kosher for Passover" or that your host approves it in advance.