The sharp U.S. market drop on 24 October 1929, the first major panic day of the Wall Street Crash, is called Black Thursday.
On 24 October, heavy selling overwhelmed the New York Stock Exchange. The Dow Jones Industrial Average fell sharply, and a large crowd gathered outside the exchange as news of the turmoil spread. A group of major bankers bought shares to support prices, temporarily calming the market.
The stabilization did not end the crash. Selling returned the following week, including the session known as Black Monday on 28 October and the even more famous Black Tuesday on 29 October. Those later days produced larger losses, but Black Thursday marked the first dramatic break in confidence.
The 1929 crash was connected to speculation, buying shares on margin, economic weakness, and excessive optimism. It contributed to the Great Depression, although the Depression had multiple causes and was not created by a single trading day.