Casings are protective coverings used in various applications, most commonly in the food industry. They are typically made from natural or synthetic materials and serve to encase products like sausages, helping to maintain their shape, flavor, and freshness. Natural casings are often made from animal intestines, while synthetic options can be made from collagen or cellulose. In addition to food, casings are also used in other fields, such as construction and electronics. For example, in construction, casings can refer to the outer coverings of windows and doors, providing insulation and aesthetic appeal. In electronics, casings protect sensitive components from damage and environmental factors.