It is the set of dietary rules that Jews have and in which they determine which foods are suitable or allowed (kosher) and which are not. They are based on the determinations set forth in Leviticus 11 and Deuteronomy 14.
Although it looks less, it is the same as the Yiddish "kosher". From Hebrew 1502; 1460; 1511; 1456; 1493; 1462; 1468; 1513; 1461; 1473; 1512; (cáshrut "which properly respects the Jewish precepts for the food that practitioners may consume" ).
KASHRUT (right or proper, in Hebrew) is part of the biblical precepts of Leviticus that determines which foods are kosher, or permitted to Jews and which are forbidden.