Passover is the seven-day holiday of the Feast of Unleavened Bread
Jewish Passover is one of the worlds most widely celebrated Jewish holiday and commemorates the biblical story of Exodus, when hebrew slaves were released from bondage in Egypt. Passover begins on the 15th day of the month of Nisan, which typically falls in March or April of the Gregorian Calender. To ensure that Passover did not start before spring, the tradition in ancient Israel held that the first day of Nisan would not start until the barley was ripe. If the barley was not ripe, this indicated that it wasn't spring yet, and an extra month would be added. Since at least the 4th century, the date has been fixed mathematically. Every year, Jews are commanded to tell the Passover story. This usually takes place during the Passover Seder, which is a service held at home as part of the Passover celebration. It is always observed on the first night of Passover, and in some homes on the second night as well. On both nights, the seder concludes with a dinner.