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; however, a variety of reported recipes and experimental recreations have been published.
Candler initiated the veil of secrecy that surrounds the formula in 1891 as a publicity, marketing, and intellectual property protection strategy. While several recipes, each purporting to be the authentic formula, have been published, the company maintains that the actual formula remains a secret, known only to a very few select (and anonymous) employees.
Information found at wikipedia.org/wiki/Coca-cola and wikipedia.org/wiki/Coca-cola_formula
Images found here, here, here, and here.