A restaurant is a business that prepares and serves food and beverages to customers. Meals are generally served and eaten on the premises, but many restaurants also offer take-out and food delivery services. Restaurants vary greatly in appearance and offerings, featuring a wide variety of cuisines and service models — ranging from inexpensive fast-food restaurants and cafeterias to mid-priced family restaurants to high-priced luxury establishments.

The word derives from the early 19th century, taken from the French word restaurer 'provide meat for', literally 'restore to a former state' and, being the present participle of the verb, the term restaurant may have been used in 1507 as a "restorative beverage", and in correspondence in 1521 to mean 'that which restores the strength, a fortifying food or remedy'.

A public eating-establishment similar to a restaurant is mentioned in a 512 BC record from Ancient Egypt. It served only one dish, a plate of cereal, wildfowl, and onions.

A forerunner for the modern restaurant is the thermopolium, an establishment in Ancient Greece or Ancient Rome that sold and served ready-to-eat food and beverages. These establishments were somewhat similar in function to modern fast-food restaurants. They were most often frequented by people who lacked private kitchens. In the Roman Empire, they were popular among residents of insulae.

In Pompeii, 158 thermopolia with service-counters have been identified throughout the town. They were concentrated along the main axis of the town and near public spaces where they were frequented by the locals.

The Romans also had the popina, a wine bar which in addition to a variety of wines offered a limited selection of simple foods such as olives, bread, cheese, stews, sausage, and porridge. The popinae were known as places for the plebeians of the lower classes of Roman society to socialize. While some were confined to one standing room only, others had tables and stools and a few even had couches.

Another early forerunner of the restaurant was the inn. Throughout the ancient world, inns were set up alongside roads to cater to people travelling between cities, offering lodging and food. Meals were typically served at a common table to guests. However, there were no menus or options to choose from.

Early eating establishments recognizable as restaurants in the modern sense emerged in Song dynasty China during the 11th and 12th centuries. In large cities, such as Kaifeng and Hangzhou, food catering establishments catered to merchants who travelled between cities. Probably growing out of tea houses and taverns which catered to travellers, Kaifeng's restaurants blossomed into an industry that catered to locals as well as people from other regions of China. As travelling merchants were not used to the local cuisine of other cities, these establishments were set up to serve dishes familiar to merchants from other parts of China. Such establishments were located in the entertainment districts of major cities, alongside hotels, bars, and brothels. The larger and more opulent of these establishments offered a dining experience similar to modern restaurant culture. According to a Chinese manuscript from 1126, patrons of one such establishment were greeted with a selection of pre-plated demonstration dishes which represented food options. Customers had their orders taken by a team of waiters who would then sing their orders to the kitchen and distribute the dishes in the exact order in which they had been ordered.