The Roaring Twenties was the period of Western society and Western culture that occurred during and around the 1920s. It was a period of sustained economic prosperity with a distinctive cultural edge in the United States and Western Europe, particularly in major cities such as Berlin, Chicago, London, Los Angeles, New York City, Paris, and Sydney. In the French Third Republic, the decade was known as the ""années folles"" ("Crazy Years"), emphasizing the era's social, artistic and cultural dynamism. Jazz music blossomed, the flapper redefined the modern look for British and American women, and Art Deco peaked. Not everything roared: in the wake of the hyper-emotional patriotism of World War I, Warren G. Harding brought back normalcy to the politics of the United States. This era saw the large-scale use of automobiles, telephones, motion pictures, radio, and electric appliances. Aviation became a business. The economies saw rapid industrial growth, accelerated consumer demand, plus significant changes in lifestyle and culture. The media focused on celebrities, especially sports heroes and movie stars, as cities rooted for their home teams and filled the new palatial cinemas and gigantic sports stadiums. In most major democratic states, women won the right to vote. 

The social and cultural features known as the Roaring Twenties began in leading metropolitan centers, then spread widely in the aftermath of World War I. The United States gained dominance in world finance. Thus, when Germany could no longer afford to pay World War I reparations to the United Kingdom, France and the other Allied Powers, the United States came up with the Dawes Plan; named after banker, and later 30th Vice President Charles G. Dawes, respectively. Wall Street invested heavily in Germany, which repaid its reparations to countries that, in turn, used the dollars to pay off their war debts to Washington. By the middle of the decade, prosperity was widespread, with the second half of the decade known, especially in Germany, as the "Golden Twenties".
What became an industry in this time?
Aviation became a business.