Coca-Cola, or Coke, is a carbonated soft drink manufactured by The Coca-Cola Company. Originally marketed as a temperance drink and intended as a patent medicine, it was invented in the late 19th century by John Stith Pemberton and was bought out by businessman Asa Griggs Candler, whose marketing tactics led Coca-Cola to its dominance of the world soft-drink market throughout the 20th century. The drink's name refers to two of its original ingredients: coca leaves, and kola nuts (a source of caffeine). The current formula of Coca-Cola remains a trade secret, although a variety of reported recipes and experimental recreations have been published. The Coca-Cola Company produces concentrate, which is then sold to licensed Coca-Cola bottlers throughout the world. The bottlers, who hold exclusive territory contracts with the company, produce the finished product in cans and bottles from the concentrate, in combination with filtered water and sweeteners. A typical can contains of sugar (usually in the form of high fructose corn syrup). The bottlers then sell, distribute, and merchandise Coca-Cola to retail stores, restaurants, and vending machines throughout the world. The Coca-Cola Company also sells concentrate for soda fountains of major restaurants and foodservice distributors. The Coca-Cola Company has on occasion introduced other cola drinks under the Coke name. The most common of these is Diet Coke, along with others including Caffeine-Free Coca-Cola, Diet Coke Caffeine-Free, Coca-Cola Zero Sugar, Coca-Cola Cherry, Coca-Cola Vanilla, and special versions with lemon, lime, and coffee. Based on Interbrand's "best global brand" study of 2015, Coca-Cola was the world's third most valuable brand, after Apple and Google. In 2013, Coke products were sold in over 200 countries worldwide, with consumers drinking more than 1.8 billion company beverage servings each day. Coca-Cola ranked No. 87 in the 2018 Fortune 500 list of the largest United States corporations by total revenue.