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Science | Military | Branches

Learn about the various branches of the U.S. Military. Find out how they were formed, their role in the nation's defense, and what it's like to be a soldier in one of these branches.


Quiz: Name That Military-free Country

Quiz: Name That Military-free Country

Believe it or not, a number of countries around the world have either disarmed their militaries or never formed one in the first place. Test your knowledge of the world's nonmilitary powers. See more »

How IARPA Works

How IARPA Works

IARPA is a U.S. government research and development organization intended to aid the U.S. intelligence community. Learn more about IARPA and its goals. See more »

How Delta Force Works

How Delta Force Works

Delta Force is the United States' most elite tactical combat group. Learn about Delta Force and the secrecy surrounding the Delta Force team See more »

How the Army Rangers Work

How the Army Rangers Work

The Army Rangers can be traced back to pre-Revolution colonial times. Read about the Army Rangers and find out why the Army Rangers were first organized. See more »

How the Green Berets Work

How the Green Berets Work

The Green Berets are America's first line of defense around the world. Learn about the role of the Green Berets and the many duties of the Green Berets. See more »

How NORAD Works

How NORAD Works

NORAD is a military operation that is jointly run by the United States and Canada. Learn about NORAD and the unique location for the NORAD headquarters. See more »

How is the National Guard different from the regular Army?

How is the National Guard different from the regular Army?

The National Guard serves many purposes and does many jobs for the United States. Learn what the National Guard is and how it differs from the Army. See more »

How the U.S. Marines Work

How the U.S. Marines Work

The Marines are the smallest branch of the military and project power from Navy ships. See more »

How the U.S. Navy Works

How the U.S. Navy Works

The U.S. Navy is the biggest in the world. It is divided into operating forces and shore establishment. See more »

How the U.S. Air Force Works

How the U.S. Air Force Works

The U.S. Air Force is the youngest American military branch, forming in the 20th century after the invention of the airplane. Learn about the history of the Air Force, how it's structured, the process of joining and leaving, and life during time served. See more »