The main purpose of the Gold Standard Act of 1900 was to establish gold as the sole backing for U.S. currency, thereby standardizing the monetary system. This act reaffirmed the U.S. commitment to the gold standard after a period of economic uncertainty and debates about bimetallism (using both gold and silver). By fixing the dollar to gold, the government aimed to create stability and confidence in the economy, promoting trade and investment. However, the gold standard also had its drawbacks, including constraining the money supply and limiting the ability to respond to financial crises, leading to economic challenges in subsequent decades.