October 29, 1929, is commonly known as Black Tuesday, the day of a historic U.S. stock-market sell-off.
The Dow Jones Industrial Average fell 12.8% that day, following a 12.3% decline on Black Monday, October 28. Trading volume reached a then-record level as investors rushed to sell shares. The crash did not single-handedly cause the Great Depression, but it became its most famous financial symbol.
The market had risen dramatically during the 1920s, supported partly by speculative buying and purchases made with borrowed money. When prices began falling, forced selling and fear intensified the decline. Banks, businesses, and households were affected by the loss of wealth and credit.
A common mix-up is treating Black Tuesday as the entire 1929 crash. It was one especially dramatic day in a broader collapse that began after the market’s September peak and continued into 1932.