In the Western Union in the 30s of the 20th century worked 14 thousand couriers delivering telegrams. In the 30's of the twentieth century, Western Union has become the world's largest telegraph company. Leaving the idea of expansion into Europe, Western Union took up the expansion of services in the U.S. market. In October 2006 the company made an initial public offering of shares on the New York Stock Exchange, becoming independent from First Data company. In 1914 Western Union engineers invented the first payment card - a prototype of the modern credit card.