The Great Depression was a severe worldwide economic downturn that lasted from 1929 to the late 1930s. It was the longest, deepest, and most widespread depression of the 20th century. The Great Depression was triggered by the stock market crash of 1929, which led to widespread unemployment, bank failures, and a general economic collapse. This period of economic hardship had a profound impact on individuals, families, businesses, and governments around the world, leading to significant social and political changes. Researchers continue to study the causes and effects of the Great Depression in order to understand how such a catastrophic event can be prevented in the future.