A guided-missile destroyer is designed to launch anti-aircraft guided missiles. Many are also equipped to carry out anti-submarine, anti-air, and anti-surface operations. The NATO standard designation for these vessels is DDG. Nations vary in their use of destroyer D designation in their hull pennant numbering, either prefixing or dropping it altogether. The U.S. Navy has adopted the classification DDG in the American hull classification system.
In addition to the guns, a guided-missile destroyer is usually equipped with two large missile magazines, usually in vertical-launch cells. Some guided-missile destroyers contain powerful radar systems, such as the United States' Aegis Combat System, and may be adopted for use in an anti-missile or ballistic-missile defense role. This is especially true for navies that no longer operate cruisers, so other vessels must be adopted to fill in the gap.
This section's factual accuracy is disputed. (October 2016) (Learn how and when to remove this template message)
Although the French Navy no longer uses the term "destroyer", the largest frigates are assigned pennant numbers with flag superior "D", which designates destroyer.