One of the most important of military courtesies is the salute.
It is a respectful greeting, a sign of recognition between military persons.
It is that, and no more. There has been a good deal of misunderstanding about the salute, most of it on the part of people who don't know how soldiers feel about it. Many civilians completely misinterpret its purpose and meaning. They take it to be an acknowledgment of the soldier's inferiority to his superiors. Noting is further from the truth. Salutes are given and returned. They are a privilege of the military alone. Every officer salutes every other officer, just as every enlisted man salutes every officer. The highest-ranking general in the Army is required to return the salute of the greenest buck private. The fact that the subordinate salutes first is simply common-sense courtesy applied to a military expression; it is for the same reason that gentlemen step aside for ladies in doorways and younger people are introduced to their elders rather than the other way around.
The salute has an additional purpose. It is evidence of respect for authority. In the Army, an officer does not determine his own authority nor just assume as much of it as he feels he should have; his authority is prescribed and becomes his duty and responsibility whether or not he likes it. In saluting, you acknowledge respect for the position and authority of the officer who holds that position.
Persons to salute
You are required to salute all commissioned officer, both male and female, of the Army, Navy, Marine Corps, and Coast Guard, and members of the Army and Navy Nurse Corps, and all warrent officers and flight officers. It is customary to salute officers of United Nations when you recognize them as such. Do not salute noncommissioned officers or petty officers.
How to salute
Make your salute smart and snappy. A half-hearted, sloppy salute
gives you away as a raw recruit. Remember your dislike of a half-hearted handshake!
The same principle applies to the salute.
To salute, raise your right hand smartly until the tip of your forefinger (index finger) touches your handgear, above above and slightly to the right of your right eye. Keep your thumb and fingers extended and joined, palm to the left, with your hand and wrist straight. Hold your upper arm horizontal, and your forearm inclined at an angle of 45º. At the same time turn your head and eyes toward the person or flag you are saluting. Hold the salute until returned by the person, saluted, then drop your hand smartly to your side (without smacking the side of your skirt).
This is the regulation salute. Learn how to do it properly. Practice in front of a mirror. Don't give your salute any extra flourishes; that is simply bad taste.