Abstract: Noble metal nanostructures possess rich optical properties due to their localized surface plasmon resonances, which can be excited by electromagnetic waves. Their unique plasmonic properties can be employed in various applications, such as renewable energy, biomedical science, national security, food safety, information technology, and metamaterials. In this article,we briefly review the properties of localized surface plasmons, plasmon coupling in noble metal nanostructures, and some of their important applications.