The sudden U.S. market plunge on May 6, 2010, was called the Flash Crash.
During the afternoon of May 6, the Dow Jones Industrial Average briefly fell nearly 1,000 points, or about 9%, before recovering much of the loss within minutes. Many individual stocks and exchange-traded products experienced extreme, short-lived price movements.
Investigations found that automated and high-frequency trading played an important role in amplifying the sell-off. A large sell order in E-mini S&P 500 futures interacted with already stressed market conditions, while liquidity rapidly disappeared from parts of the market.
The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission later described the event as a complex interaction of algorithmic trading, liquidity, and market structure. The crash prompted safeguards including circuit breakers and rules designed to pause trading during unusually rapid price moves.