The military uses several types of flags, streamers, and guidons. Each military branch does have a unique flag but also uses the national color, with a golden fringe, on a frequent basis. Guidons are used by units within the military, representing their duties and heritage. Streamers allocated to the units signify some special accomplishments. Each branch, however, has to use the right military flags based on military protocol dictating different uses for five different sizes of the flag.
Main types
Branch flags
The air force, army, navy, coast guard, and Marine Corps each have a unique 
flag. The branch flag is usually flown next to the national color or American flag during some displays or ceremonies. The rules dictate that the branch flag must be flown to the right side of the American flag with reference to the observer’s view if they are to be flown alongside each other. This rule applies to all the other flags as well such that in a ceremony, the national color or American flag will always appear to the far left.
National colors
Also referred to as The Colors, the national flag colors are used for indoor display and in formal ceremonies. The Colors are fringed on three sides with gold, with the side that is used for hoisting having no fringes. Similar to the American flag, the colors are also flown on the left side of the observer, if flown alongside any other flag. The ordinary American flag and the Colors can never appear together. Only the Color Guard, an official party who is usually designated by a unit commander, is allowed to carry the Colors during ceremonies.
Guidons
Guidons are simply unit designators. Armies have been known to carry compact flags or guidons that are unique to their unit, since the ancient times. The primary purpose of the guidon is to announce military affiliations. The tradition was brought to the US troops back in the 18th century by a trainer known as Friedrich. The guidon is carried by each unit of the military during displays, ceremonies, and at posts in combat zones outside headquarters.
American flag
They are the most widely used in the military. Every military installation flies an eight-foot, 11 3/8-inch by 17-foot post flag on a regular basis. Even during snow or rain, a storm flag will still be raised. The flag is also usually given to the families of diseased members of the service.