The Great Depression
The Great Depression refers to a period in US history, from 1929 to 1941, when America's economy was not working. Many banks failed, people lost their homes and their farms. The Great Depression was worldwide, although it hit the USA the hardest and the longest.
Although there had been economic depressions before, the 1930s depression was the most devastating, affecting over half of the population, both rich and poor, from all walks of life, in both urban and rural sections of the country. That is why it is called the Great Depression, not because things were great, but because things were ruinous for so many people.
See Also: The New Deal