A cheeseburger is a hamburger with a slice of cheese, typically American, cheddar, or Swiss, melted onto the beef patty before serving on a bun with standard burger toppings and condiments. Its invention is disputed; the most commonly repeated origin story credits a Pasadena, California sandwich shop in the late 1920s, though other claims exist. It is a fixture of American fast-food and diner culture and is now made worldwide, including with turkey, chicken, or plant-based patties.