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, and ghost restaurants.
Restaurants range from inexpensive and informal lunching or dining places catering to people working nearby, with modest food served in simple settings at low prices, to expensive establishments serving refined food and fine wines in a formal setting. In the former case, customers usually wear casual clothing. In the latter case, depending on culture and local traditions, customers might wear semi-casual, semi-formal or formal wear. Typically, at mid- to high-priced restaurants, customers sit at tables, their orders are taken by a waiter, who brings the food when it is ready. After eating, the customers then pay the bill. In some restaurants, such as workplace cafeterias, there are no waiters; the customers use trays, on which they place cold items that they select from a refrigerated container and hot items which they request from cooks, and then they pay a cashier before they sit down. Another restaurant approach which uses few waiters is the buffet restaurant. Customers serve food onto their own plates and then pay at the end of the meal. Buffet restaurants typically still have waiters to serve drinks and alcoholic beverages. Fast food restaurants are also considered a restaurant. In addition, food trucks are another popular option for people who want quick food service.
Tourists around the world can enjoy dining services on railway cars and cruise ships dining rooms, which are essentially traveling restaurants. Many railways dining services cater to the needs of travelers by providing railway refreshment rooms at railway stations. Many cruise ships provide a variety of dining experiences including a main restaurant, satellites restaurants, room service, specialty restaurants, cafes, bars, and buffets to name a few. Some restaurants on these cruise ships required table reservations and specific dress codes.