The document summarizes technological advances in the 1920s like the development of radio broadcasting and networks, as well as advances in aviation such as transatlantic flights. It then discusses the onset of the Great Depression in the US starting in 1929. Key events included a 50% drop in farm income between 1929-1932, industry operating at half capacity, and over 12 million Americans becoming unemployed by 1932, representing a quarter of the workforce. President Hoover opposed direct federal relief and launched public works programs to address unemployment, but the worldwide scope of the Great Depression prevented any recovery.