In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. In the 30's of the twentieth century, Western Union has become the world's largest telegraph company. In 1933, by the Western Union Company were invented "singing telegrams". Sibley, the founder of Western Union, did not build a new telegraph lines, and persuaded the other players to join. American Telegraph Company, however, still had to buy it.