Marine customs are simply desirable courses of action sanctioned by tradition and usage. In the Marine Corps, practically every custom has grown out of the manner in which Marines of the past conducted themselves. Many Marine customs have been incorporated into regulations in order to standardize conduct throughout the Corps, but some of them cannot be found in written directives. Knowing and observing these customs, both written and unwritten, is important to each Marine because it keeps him mindful of the heritage and traditions of his Corps, and of his duty to uphold them. In addition, it makes him feel that he is a part of the team and helps to create the strong bond of loyalty between him and all other Marines that has become a distinguishing mark of the Corps.
Marine Corps Birthday. One of the most famous Marine customs is the observance of the Marine Corps Birthday. Since 1921 the birthday of the Marine Corps has been officially celebrated each year on 10 November, since it was on this date in 1775 that Continental Congress resolved, "That two Battalions of Marines be raised...." Over the years the Marine Corps Birthday has been celebrated in a wide variety of ways, depending on the location and circumstances of the Marine units. The celebration involves the reading of an excerpt from the Marine Corps Manual and a birthday message from the Commandant; the cutting of a birthday cake by the commanding officer; and the presentation of the first and second pieces of cake to the oldest and youngest Marines present. Recently, the ceremony for the observance of the Marine Corps Birthday by large posts and stations has been incorporated into written directives.
Nautical Terms. Many of the Marine Corps customs are derived from the many years of service afloat. Even ashore Marines customarily use nautical terms. Floors are "decks," walls are "bulkheads," ceilings, "overheads," corridors, "passageways." The order "Gangway!" is used to clear the way for an officer ashore, just as it is afloat. Among other terms in common usage are: "two-block" -to tighten or center (as a necktie); "square-away" - to correctly arrange articles or to take in hand and direct an individual;" "head" - a bathroom; "scuttle-but" -a drinking fountain, also an unconfirmed rumor.
In the Marine Corps, the nautical expression "Aye, Aye, Sir" is used when acknowledging a verbal order. "Yes, Sir" and "No, Sir" are used in answer to direct questions. "Aye, Aye, Sir" is not used in answer to questions as this expression is reserved solely for acknowledgement of orders.
Reporting Your Post. A custom which affects the guard is the manner in which a sentry reports his post to the officer of the day, or to the officers and noncommissioned officers of the guard. The customary procedure is for the sentry to salute or come to present arms and say, "Sir, Private ______________ reports Post Number ____ all secure. Post and orders remain the same. Nothing unusual to report." This custom has almost universal use throughout the Marine Corps. It is a convenient, useful form, and thus it has been preserved by custom, and passed on by word of mouth.
Salutes. Some of the most important customs of all are those of military courtesy. In the Marine Corps, courtesy is an expression of respect for the authority possessed by an individual, as well as a demonstration of respect for the Corps as a whole. Through the use of the various forms of military courtesy a Marine says, in effect, "As brothers in arms and fellow Marines, I consider you worthy of my respect." When used in this manner, military courtesy assumes one of its most important roles; it is an expression of the respect a Marine has for other Marines and for himself. Of all the forms of military courtesy, the various salutes are probably the most important. They are certainly the most obvious and frequently used. Saluting is the traditional form of greeting between men of the profession of arms and it is an honored tradition of military organization throughout the world.