The 24 October 1929 trading day in the New York stock-market crash was nicknamed Black Thursday.
On that Thursday, roughly 12.9 million shares changed hands on the New York Stock Exchange, a record at the time. Prices dropped sharply in early trading, but a group of major bankers and financiers bought large quantities of leading stocks and temporarily steadied the market. The apparent rescue did not end the underlying panic.
Selling returned the following week. Black Monday occurred on 28 October, and Black Tuesday followed on 29 October. The Dow’s fall on those two days was especially severe, helping turn a market break into the defining crash of the era. The market then continued to decline for years before reaching its major low in 1932.
Black Thursday is sometimes confused with Black Tuesday because Tuesday produced the larger volume and a major percentage fall. The names refer to different dates in the same 1929 episode, not to separate historical crashes.