When you buy a sandwich or cookie from a bakery or café, it’s often wrapped in a special kind of paper that doesn’t let oil or sauce leak through. This is called greaseproof paper, and it’s very common in restaurants. It keeps food fresh and makes it easier to eat without a mess. It’s used by food trucks, cafes, takeout spots, and bakeries. The reason this paper works so well is because of how it’s made. The fibers in the paper are pressed together really tightly, so oil and water can’t pass through. Some kinds also have a thin layer of wax or a safe coating on them. That’s why even if the food is greasy or juicy, the paper doesn’t break or soak through.