A person is considered to be on active duty if they are on full-time duty in the U.S. Armed Forces. Active duty does not include training in the Reserve or National Guard but does include activation from the Reserve or National Guard.
A person is considered to be in the Armed Forces if they currently serve on Active Duty in any branch of the U.S. military. This includes the Army, Navy, Marine Corps, Air Force, Space Force, and Coast Guard; their reserve components; and the Air and Army National Guard.