A restaurant prepares and serves food, drink and dessert to customers. Meals are generally served and eaten on premises, but many restaurants also offer take-out and food delivery services. Restaurants vary greatly in appearance and offerings, including a wide variety of cuisines and service models.

While inns and taverns were known from antiquity, these were establishments aimed at travellers, and in general locals would rarely eat there. Modern restaurants, as businesses dedicated to the serving of food, and where specific dishes are ordered by the guest and generally prepared according to this order, emerged only in 18th-century Europe, although similar establishments had also developed in China.

A restaurant owner is called a restaurateur; both words derive from the French verb restaurer, meaning "to restore". Professional artisans of cooking are called chefs, while prep staff and line cooks prepare food items in a more systematic and less artistic fashion.

There are various types of restaurants. Restaurants fall into several industry classification based upon menu style, preparation methods and pricing. Additionally, how the food is served to the customer helps to determine the classification.

Historically, restaurant referred only to places that provided tables where one sat down to eat the meal, typically served by a waiter. Following the rise of fast food and take-out restaurants, a retronym for the older "standard" restaurant was created, sit-down restaurant. Most commonly, "sit-down restaurant" refers to a casual dining restaurant with table service rather than a fast-food restaurant where one orders food at a counter. Sit-down restaurants are often further categorized as "family-style" or "formal".

In British English, the term restaurant almost always means an eating establishment with table service, so the "sit-down" qualification is not usually necessary. Fast food and takeaway (takeout) outlets with counter service are not normally referred to as restaurants. Outside of North-America the terms Fast casual-dining restaurants, Family style, and Casual dining are not used. Junk food establishments would also not often be referred to as a 'restaurant'.

Restaurant guides review restaurants, often ranking them or providing information for consumer decisions (type of food, handicap accessibility, facilities, etc). In 12th century Hanzhou (mentioned above as the location of the first restaurant), signs could often be found posted in the city square listing the restaurants in the area and local customer's opinions of the quality of their food. This was an occasion for bribery and even violence. Today, restaurant review is carried out in a more civilized manner. One of the most famous contemporary guides, in Western Europe, is the Michelin series of guides which accord from 1 to 3 stars to restaurants they perceive to be of high culinary merit. Restaurants with stars in the Michelin guide are formal, expensive establishments; in general the more stars awarded, the higher the prices. The main competitor to the Michelin guide in Europe is the guidebook series published by Gault Millau. Unlike the Michelin guide which takes the restaurant décor and service into consideration with its rating, Gault Millau only judges the quality of the food. Its ratings are on a scale of 1 to 20, with 20 being the highest.

In the United States, the Forbes Travel Guide (previously the Mobil travel guides) and the AAA rate restaurants on a similar 1 to 5 star (Forbes) or diamond (AAA) scale. Three, four, and five star/diamond ratings are roughly equivalent to the Michelin one, two, and three star ratings while one and two star ratings typically indicate more casual places to eat. In 2005, Michelin released a New York City guide, its first for the United States. The popular Zagat Survey compiles individuals' comments about restaurants but does not pass an "official" critical assessment. In the United Kingdom, diners can freely express their opinion on where they eat in The people's UK restaurant guide. In the United States Gault Millau is published as the Gayot guide, after founder Andre Gayot. Its restaurant ratings use the same 20 point system, and are all published online.

The Good Food Guide, published by the Fairfax Newspaper Group in Australia, is the Australian guide listing the best places to eat. Chefs Hats are awarded for outstanding restaurants and range from one hat through three hats. The Good Food Guide also incorporates guides to bars, cafes and providers. The Good Restaurant Guide is another Australian restaurant guide that has reviews on the restaurants as experienced by the public and provides information on locations and contact details. Any member of the public can submit a review.

Nearly all major American newspapers employ food critics and publish online dining guides for the cities they serve. A few papers maintain a reputation for thorough and thoughtful review of restaurants to the standard of the good published guides, but others provide more of a listings service.

More recently Internet sites have started up that publish both food critic reviews and popular reviews by the general public. Their major competition comes from bloggers, particularly publishers of food blogs, also called foodies. These writers and publishers represent the common dining aficionado rather than the gourmet, and thus do not provide "official" reviews, but nonetheless are capable of garnering large, loyal followings.

Restaurant ratings identify restaurants according to their quality, using various notations such as stars or other symbols, or numbers. Stars are a familiar and popular symbol, with ratings of one to four or five stars commonly used. Ratings appear in guidebooks as well as in the media, typically in newspapers, lifestyle magazines and webzines. Websites featuring consumer-written reviews and ratings are increasingly popular.

In addition, there are ratings given by public health agencies rating the level of sanitation practiced by an establishment. These ratings are given from a numerical scale, with 100 being a perfect score and points deducted for each violation, such as keeping food at the wrong temperature, roach/vermin/rodent infestation, failure to use NSF-certified equipment, or improper food storage. From that, a grade is often assigned.