The Great Depression in the United States began with the stock market crash on October 29, 1929, commonly known as Black Tuesday. This catastrophic event led to a severe economic downturn that lasted throughout the 1930s. The crash wiped out millions of investors, triggered massive bank failures, and resulted in high unemployment rates and widespread poverty. The effects of the Great Depression were profound, leading to significant changes in government policy, the New Deal programs under President Franklin D. Roosevelt, and an eventual shift in the economy that shaped the course of American history.