Restaurants may be categorized or distinguished in various different ways.

The basic factors are generally the food itself (for instance vegetarian, steak, seafood); the cookery (e.g. Japanese, Italian, Chinese, French, Indian, Mexican, and Thai) and/or the version of offering (e.g. a sushi train, tapas bar, a buffet restaurant, a tastet restaurant, or a yum cha restaurant). Surpassing this, restaurants may distinguish themselves on features including speed, location, formality, cost, novelty themes or service.

Restaurants vary from inexpensive and informal dining or lunching places serving people working adjacent, with simple food served in simple establishments at small prices, to costly settings serving high-class fine wines and foods in an official establishment. In the preceding case, clients normally wear informal clothing. In the latter case, reliant on local conventions and culture, customers might wear semi-informal, semi-formal or formal wear. Generally, clienteles sit at tables; their orders are taken by a server, who delivers the food when it is ready. As soon as they finish eating, the clients then pay the bill.

For some time the touring public has been supplied for with ship's eateries and railway restaurant cars which are, in effect, travelling restaurants. Several railways, across the globe, also supply for the wants of tourists by offering Railway Refreshment Rooms [a form of restaurant] at railway destinations. In modern times there has been a trend to construct a number of travelling restaurants, especially made for tourists. These can be gotten on such varied places as boats, trams, buses and many others.