Kosher (from Hebrew kāshēr,”fit, proper”), term meaning ritually proper for use according to Jewish law. It is applied especially to the food that Jews are permitted to eat under dietary laws that are derived from passages in the biblical books of Leviticus and Deuteronomy. According to the Bible only animals that have cloven hooves and are ruminant, that is, chew the cud, are considered kosher (see Deuteronomy 14:3-21). Thus, pork and other products from hogs are considered unfit. The animals that are acceptable must be killed according to the traditional rabbinical ritual and soaked, salted, and washed to remove any traces of blood. Milk or milk products must not be eaten with meat, and shellfish is to be avoided. Dishes and cooking utensils used for preparing and serving meat must not be used for preparing and serving milk or milk products, nor can dishes and utensils used for milk be used for meat. During the festival of Passover, no leavened bread is to be eaten, and a set of dishes and cooking utensils is to be reserved specifically for use during this holiday. These dietary regulations were originally designed to preserve health standards, and today they are followed primarily by observant, religious Jews.