On August 31, 1949, Louis Johnson, who was the United States Secretary of Defense, announced the creation of an Armed Forces Day to separate Army, Navy and Air Force Days. Armed Forces Day is on the third Saturday of May. It is a day to pay tribute to men and women who serve the United States armed forces. It is also a part of Armed Forces Week, which begins on the second Saturday of May.

Many events across the United States take place on Armed Forces Day to honor Americans in uniform who served their country in times of war and peace. Those who are honored on this day include people who serve the Army, Navy, Marines, Air Force, Coast Guard, and, National Guard. People celebrate this day in many ways all over the world.

The U.S. celebrates by organizing multi-service military displays in areas open for the public. They schedule different educational activities that teach children about the armed forces. They sponsor “Support the Troops” themed motorcycle rides. They even have large parades and local celebrations.

Source: http://www.timeanddate.com/holidays/us/armed-forces-day