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.
Food and drink prohibitions
Certain species of fish are also forbidden in Judaism such as the freshwater eel (Anguillidae) and all species of catfish. Although they live in water, they appear to have no scales (except under a microscope) (see Leviticus 11:10-13). Sunni Muslim laws are more flexible in this. Catfish and shark are generally seen as halal as they are special types of fish. Eel is generally considered permissible in the four Sunni "madh'hab." The Ja'fari jurisprudence followed by most Shia Muslims forbid all species of fish that does not have scales, it also forbid all shell fish species except prawns.