There are many Jewish laws for the preparation of food. These laws come from Kashrut, the part of Jewish law dealing with foods that can and cannot be eaten. The word kosher is more commonly used to describe these rules. A common misconception is that kosher is a style of cooking. Any type of food can be kosher, as long as it is prepared according to the laws of the Torah. Treyf is a word used commonly to describe food that is not kosher.
For some modern Jews, the kosher laws are nothing more than a series of health regulations. While keeping the kosher laws is certainly healthy, health is not the only reason for them. The main reason as to why Jewish peop