The 2010 United States Flash Crash occurred on May 6, 2010, when major indexes plunged and quickly recovered.
During the afternoon of May 6, U.S. equity markets experienced an exceptionally rapid decline. The Dow Jones Industrial Average fell about 1,000 points, or nearly 9%, before recovering much of the loss within minutes.
Investigations linked the event to interactions among high-frequency trading, automated orders, market liquidity, and a large sell order in stock-index futures. Some individual securities briefly traded at extremely low or high prices.
The event led regulators to review market structure and introduce or strengthen safeguards, including circuit breakers and rules for clearly erroneous trades. It is called a flash crash because the most dramatic movement happened over a very short period, unlike the prolonged declines of 1929 or 2008.