Restaurants are classified or distinguished in many different ways. The primary factors are usually the food itself (e.g. vegetarian, seafood, steak); the cuisine (e.g. Italian, Chinese, Japanese, Indian, French, Mexican, Thai) or the style of offering (e.g. tapas bar, a sushi train, a tastet restaurant, a buffet restaurant or a yum cha restaurant). Beyond this, restaurants may differentiate themselves on factors including speed (see fast food), formality, location, cost, service, or novelty themes (such as automated restaurants). Some of these include fine dining, casual dining, contemporary casual, family style, fast casual, fast food, cafes, buffet, concession stands, food trucks, pop-up restaurants, diners, and ghost restaurants.