The eight-day Jewish holiday of Passover begins at sundown today. Families will gather around the table for a seder, a traditional meal and prayer service commemorating the exodus of Jewish slaves out of Egypt. It follows the story of Moses, who according to the Old Testament, convinced the Pharaoh to free the Jews after unleashing ten plagues including the killing of the first born son. Moses warned the Jews, if they marked their door with lamb’s blood, the plague would just “pass over” and spare their children. Jews traditionally eat Matzo, or unleavened bread, during the holiday. It’s in remembrance of how when their ancestors fled Egypt, they left in such haste that the bread they packed didn’t have time to rise.