Fast food chains are restaurants that serve quick, convenient meals, often with a focus on speed and efficiency. They typically offer a limited menu of items such as burgers, fries, and soft drinks, allowing customers to order and receive their food rapidly. Popular examples include McDonald's, Burger King, and KFC. These establishments are usually part of a larger franchise system, meaning they have multiple locations that follow the same branding and menu. Fast food chains are known for their affordability and consistency, making them a popular choice for people looking for a quick meal on the go.