Fast food is the term given to many items that can be prepared and served quickly. While any meal with low preparation time can be considered to be fast food, such as TV dinners, typically the term refers to food sold in a restaurant or store which is rapidly prepared and served to the customer in a packaged form for take out/take away. The term "fast food" was recognized in a dictionary by Merriam-Webster in 1951.

Outlets may be stands or kiosks, which may provide no shelter or seating, or fast food restaurants (also known as quick service restaurants). Franchise operations which are part of restaurant chains have standardized foodstuffs shipped to each restaurant from central locations.

The capital requirements to start a fast-food restaurant are relatively small, particularly in areas with non-existent or poorly enforced health codes. Small, individually-owned fast-food restaurants have become common throughout the world. Fast food restaurants with higher sit-in ratios, where customers can sit and have their orders brought to them, are known as fast casual restaurants.