The market event on May 6, 2010, when U.S. stocks plunged and rapidly rebounded, was the Flash Crash.
During the afternoon, major U.S. equity indexes and individual securities fell extremely quickly before recovering much of the loss. The Dow Jones Industrial Average briefly dropped by almost 1,000 points, then rebounded within minutes.
Investigations found that automated trading and a large sell order contributed to the turmoil, although the event reflected several interacting market-structure weaknesses. Regulators later introduced safeguards including circuit breakers and tighter controls on extreme price movements.
The Flash Crash is distinct from a conventional bear market. It was a short-lived episode of extraordinary intraday volatility, rather than a prolonged collapse caused by a broad economic downturn.