The financial crisis of 2008-2009 was caused by factors like mortgage lending and the collapse of investment banks, leading to job losses and financial turmoil. The crisis affected global markets, causing production volumes to drop, unemployment to rise, and prices to fall. The US government took steps to address the crisis, but its root cause was the Federal Reserve's policy on the overproduction of the US dollar. This crisis was the largest since the Great Depression, highlighting the need to understand its causes and consequences to prevent similar crises in the future.