Segregation is the practice of keeping raw materials, ingredients, or products apart from each other to avoid contamination. In food safety it is fundamental: raw meat is stored below and away from ready-to-eat foods, allergen-containing ingredients are kept separate from allergen-free ones, and cleaning chemicals never share space with food. Colour-coded equipment, separate storage areas, and dedicated production scheduling all enforce it. The principle extends to people and process flows, with staff and product moving from dirty to clean areas without backtracking. Failures of segregation cause some of the worst food incidents, from allergen cross-contact to pathogen transfer. It is simple in concept and demanding in discipline, and auditors check it first.