What is a stock market crash?

📘 In Brief A stock market crash is a sudden, massive, and usually unexpected decline in stock prices that often destroys large portions of market value within a few days or even hours. Common causes include speculative excesses, bursting bubbles, economic shocks, or panic-driven selling behavior that reinforces itself. Unlike a normal correction, which amounts to only a few percent, experts speak of a crash when the overall index suffers double-digit losses. The dynamic is fueled by modern trading systems that automatically sell within fractions of a second when prices fall, further accelerating the downward spiral. For investors, a crash does not automatically mean a total loss, as stock values often recover over years after such events. What matters is that a crash reflects collective fear of losses and not necessarily the actual economic situation, but rather its expected deterioration. 🔍 Why This Matters A stock market crash refers to an abrupt, massive, and usually unexpected decline in prices on securities markets that often unfolds over just a few trading days or even hours. It is characterized by a double-digit percentage drop in leading indices, triggered by panic selling orders that can reinforce themselves. Common causes include bursting speculative bubbles, systemic shocks such as bank failures, or external events like wars or pandemics that suddenly destroy confidence in asset valuations. The dynamics of a crash differ from a normal correction in terms of speed and the breadth of selling pressure, which also affects fundamentally sound companies. Modern trading algorithms and derivatives can further accelerate the downward movement, as automatic hedging strategies and margin calls lead to f …