A supermarket, a form of grocery store, is a self-service store offering a wide variety of food and household merchandise, organized into departments. It is larger in size and has a wider selection than a traditional grocery store, also selling items typically found in a convenience store, but is smaller and more limited in the range of merchandise than a hypermarket or big-box store.

The supermarket typically comprises meat, fresh produce, dairy, and baked goods departments, along with shelf space reserved for canned and packaged goods as well as for various non-food items such as household cleaners, pharmacy products and pet supplies. Most supermarkets also sell a variety of other household products that are consumed regularly, such as alcohol (where permitted), medicine, and clothes, and some stores sell a much wider range of non-food products.

The traditional suburban supermarket occupies a large amount of floor space, usually on a single level. It is usually situated near a residential area in order to be convenient to consumers. Its basic appeal is the availability of a broad selection of goods under a single roof, at relatively low prices. Other advantages include ease of parking and frequently the convenience of shopping hours that extend far into the evening or even 24 hours a day. Supermarkets usually allocate large budgets to advertising, typically through newspapers. They also present elaborate in-store displays of products. The stores are usually part of corporate chains that own or control (sometimes by franchise) other supermarkets located nearby—even transnationally—thus increasing opportunities for economies of scale.