The term unleavened bread can refer to breads which are not prepared with leavening agents. These flatbreads holds special religious significance to adherents of Judaism and Christianity. Jews consume unleavened breads such as Matzo during Passover. They are also used in the Christan liturgy when Christians perform the Eucharist, a rite derived from the Last Supper when Jesus broke bread with his disciples during a Passover Seder.  enterobacterium (src: Wikipedia)