Examines the United States' involvment in the Vietnam War, detailing key events and notable people, discussing incidents leading up to the war, and the aftermath of the war.
Explains the office of the presidency in the United States, including its history, how presidential elections are run, and the kinds of things the president is responsible for.
Discusses the use of unmanned aerial vehicles known as drones, from the aircraft's military uses to its emergence in the private sector, and describes how drones can be used for environmental protecti
