The Wall Street panic session on October 24, 1929, was known as Black Thursday.
Trading opened with heavy selling on the New York Stock Exchange after months of speculative activity and weakening confidence. A group of leading bankers attempted to stabilize prices by buying selected stocks, temporarily calming the market. The intervention did not end the broader crisis, however, and selling returned in the days that followed.
Black Thursday was followed by Black Monday on October 28 and Black Tuesday on October 29. The Dow Jones Industrial Average fell sharply across those sessions, although the market did not reach its ultimate low until July 1932. The crash helped mark the beginning of the long economic contraction later called the Great Depression.
A common mistake is to use Black Tuesday for every October 1929 event. Black Tuesday specifically refers to October 29, while Black Thursday identifies the first major panic day on October 24. The labels describe separate sessions within the same crash.