Dietary laws are the rules governing which foods the members of a particular religion are permitted or forbidden to eat, and how permitted foods must be prepared. Judaism’s kashrut forbids pork and shellfish, requires the separation of meat and dairy, and mandates specific slaughter methods; Islam’s halal rules forbid pork, blood, and alcohol and require invocation and humane slaughter; Hindu traditions commonly avoid beef; Buddhism often prescribes vegetarianism. These are not preferences but obligations, carrying deep spiritual and communal meaning. For the food industry they create entire market segments and certification systems — kosher and halal certification, with their auditors, slaughter standards, and labelling marks, are global businesses. Manufacturers serving these markets must control ingredients, processing lines, and cleaning to certification standards, making dietary law one of religion’s most tangible intersections with food technology.