On October 19, 1987, Wall Street experienced one of the most significant single-day declines in stock market history. Known as Black Monday, the Dow Jones Industrial Average plummeted by over 22%, marking the largest one-day percentage drop in history. The crash sent shockwaves through financial markets worldwide and sparked fears of an impending economic collapse. Despite the panic, the market eventually recovered, serving as a reminder of the resilience of the stock market in the face of adversity. Another notable day in stock market history is October 29, 1929, also known as Black Tuesday. This fateful day marked the beginning of the Great Depression, as the stock market crashed, leading to widespread financial ruin and economic hardship. The Dow Jones Industrial Average dropped by over 12%, signaling the start of a prolonged period of economic downturn that would last for years. The effects of Black Tuesday reverberated throughout the global economy, underscoring the interconnectedness of financial markets and the devastating impact of unchecked speculation. More recently, on September 15, 2008, Lehman Brothers, one of the oldest and largest investment banks in the United States, filed for bankruptcy. The collapse of Lehman Brothers triggered a financial crisis that would come to be known as the Great Recession. Stock markets around the world plunged, credit markets froze, and unemployment soared as the global economy teetered on the brink of collapse. The events of September 15, 2008, served as a stark reminder of the fragility of the financial system and the dangers of excessive risk-taking in the pursuit of profit. These historic days in stock market history serve as sobering reminders of the inherent risks and uncertainties of investing. While the stock market has historically provided attractive returns over the long term, it is also subject to periods of extreme volatility and instability. By studying past events and learning from the mistakes of the past, investors can better navigate the complexities of the stock market and make informed decisions that align with their financial goals and risk tolerance.