Kashrut
Among the numerous laws that form "kashrut" are prohibitions on the consumption of certain animals (such as pork and shellfish), mixtures of meat and milk, and the commandment to slaughter mammals and birds according to a process known as "shechita". There are also laws regarding agricultural produce that might impact the suitability of food for consumption.
List of halal and kosher fish
When a (kosher) fish is removed from the water, it is considered "slaughtered," and it is unnecessary to ritually kill it in the manner of kosher livestock. However, kosher law explicitly forbids the consumption of a fish while it is still alive. Talmudic law proscribes against cooking fish together with meat, or fish with actual milk (or in certain communities fish with any dairy) for health reasons, though fish may be eaten together with meat in a meal if they are in separate dishes or courses. The same applies to consuming fish and actual milk, or fish and other dairy products, within the same meal in the respective communities who prohibit cooking them together.