The word kosher is a variation of the Hebrew word meaning "fit" or "proper."
Simply put, kosher foods meet the dietary requirements of and are prepared in accordance with Jewish Law.
The determination of kosher and non-kosher foods depends on two variables: the source of the ingredients and the status of the production equipment.
Kosher certification, which is the guarantee that the food meets kosher requirements, revolves around both of the above criteria.
Shellfish such as shrimp and lobster are prohibited.
To be Kosher, a species of fish must have both scales and fins, which leaves out fish such as swordfish, sturgeon, catfish, and eel.