1) The Age of Exploration, during the 15th and 16th centuries, saw European explorers such as Christopher Columbus and Vasco da Gama reach new lands and establish trade routes.

2) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

3) The world's largest volcano, Mauna Loa in Hawaii, is also one of the most active.

4) The destructive power of cyclones is often attributed to their storm surge, which is a rise in sea level caused by the strong winds and low atmospheric pressure.