Cranberries are low, creeping shrubs or vines up to 2 metres (7 ft) long and 5 to 20 centimetres (2 to 8 in) in height; they have slender, wiry stems that are not thickly woody and have small evergreen leaves. The flowers are dark pink, with very distinct reflexed petals, leaving the style and stamens fully exposed and pointing forward. They are pollinated by bees. The fruit is a berry that is larger than the leaves of the plant; it is initially white, but turns a deep red when fully ripe. It is edible, with an acidic taste that can overwhelm its sweetness.

Cranberries are a major commercial crop in certain American states and Canadian provinces (see cultivation and uses below). Most cranberries are processed into products such as juice, sauce, jam and sweetened dried cranberries, with the remainder sold fresh to consumers. Cranberry sauce is regarded as an indispensable part of traditional American and Canadian Thanksgiving menus and some European winter festivals.

Since the early 21st century within the global functional food industry, raw cranberries have been marketed as a "superfruit" due to their nutrient content and antioxidant qualities.^{[dead link]}