The 24 October 1929 trading day was called Black Thursday, and panic selling on it helped begin the Wall Street Crash.
The Dow Jones Industrial Average fell sharply that morning as investors rushed to sell shares. A group of major bankers later pooled money to buy leading stocks, temporarily stabilizing prices and creating the impression that the crisis had been contained.
That calm did not last. Heavy selling returned on the following Monday and Tuesday, culminating in Black Tuesday on 29 October. The crash then continued for years, with the Dow eventually reaching its low in July 1932.
Black Thursday is sometimes mistakenly treated as the single day of the crash. In reality, the 1929 collapse unfolded through a sequence of severe declines, and the labels Black Thursday, Black Monday, and Black Tuesday describe different stages of the same wider breakdown.