French fries are served hot, either soft or crispy, and are generally eaten as part of lunch or dinner or by themselves as a snack, and they commonly appear on the menus of diners, fast food restaurants, pubs, and bars. They are usually salted and, depending on the country, may be served with ketchup, vinegar, mayonnaise, tomato sauce, or other local specialties. Fries can be topped more heavily, as in the dishes of poutine or chili cheese fries. Chips can be made from sweet potatoes instead of potatoes. A baked variant, oven chips, uses less oil or no oil.