The rapid 2010 U.S. market plunge and rebound that lasted about 36 minutes is called the flash crash.
On May 6, 2010, major U.S. stock indexes suddenly dropped and then recovered much of the loss within minutes. The Dow Jones Industrial Average briefly fell nearly 1,000 points, its largest intraday point decline at that time. Many individual securities also experienced extreme, short-lived price movements.
Investigations found that automated high-frequency trading and a large sell order in the E-mini S&P 500 futures market interacted with already-fragile market conditions. The event exposed weaknesses in market structure, liquidity, and automated safeguards. Regulators subsequently strengthened circuit breakers and other controls.
A flash crash is not the same as a conventional bear market. A bear market is a prolonged decline, while a flash crash is defined by extraordinary speed and abrupt reversals. The 2010 event was short-lived, even though it revealed serious systemic risks.