Final answer:
Black Tuesday is the day when the American stock market collapsed and marked the beginning of the Great Depression.
Step-by-step explanation:
The day known as the start of the Great Depression, when the American stock market collapsed, is called Black Tuesday. It occurred on October 29, 1929. On this day, stock prices plummeted and many investors lost a significant amount of money. This event led to a severe economic downturn and had long-lasting effects on the global economy.
Learn more about The start of the Great Depression