The Institute of Heraldry, officially The Institute of Heraldry, Department of the Army, is an activity of the Administrative Assistant to the Secretary of the Army solely responsible for furnishing heraldic services to the President of the United States and all federal government agencies. Title 18 of the United States Code, Chapter 33, Section 704 and Title 32 of the Code of Federal Regulations, Part 507 permit the institute to issue directives on how military insignia are displayed, the criteria for issuance, and how insignia will be worn on military uniforms.

In heraldry, the term star may refer to any star-shaped charge with any number of rays, which may appear straight or wavy, and may or may not be pierced. While there has been much confusion between the two due to their similar shape, a star with straight-sided rays is usually called a mullet in English heraldry while one with wavy rays is usually called an estoile.