Kashrut

Kashrut (also kashruth or kashrus, כַּשְׁרוּת) is the set of Jewish dietary laws. Food that may be consumed according to halakha (Jewish law) is termed kosher in English, from the Ashkenazi pronunciation of the Hebrew term kashér (כָּשֵׁר), meaning "fit" (in this context, fit for consumption). Food that is not in accordance with Jewish law is called treif (Yiddish: טרײף or treyf, derived from Hebrew טְרֵפָה trēfáh). Kosher can also refer to anything that is fit for use or correct according to halakha, such as a hanukiyah (candelabra for Hannukah), or a sukkah (a Sukkot booth). The word kosher has become English vernacular, a colloquialism meaning proper, legitimate, genuine, fair, or acceptable.

Among the numerous laws that form part of kashrut are the prohibitions on the consumption of unclean animals (such as pork, shellfish (both Mollusca and Crustacea) and most insects, with the exception of crickets and locusts), mixtures of meat and milk, and the commandment to slaughter mammals and birds according to a process known as shechita. Most of the basic laws of kashrut are derived from the Torah's Books of Leviticus and Deuteronomy. Their details and practical application, however, is set down in the oral law (eventually codified in the Mishnah and Talmud) and elaborated on in the later rabbinical literature. While the Torah does not state the rationale for most kashrut laws, many reasons have been suggested, including philosophical, practical and hygienic.