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A destroyer is a fast, manoeuvrable warship designed to escort larger vessels, originally conceived in the late 19th century to defend against torpedo boats, with the term formally shortened to "destroyer" by World War I. After World War II, these ships grew dramatically in size and power, with the American Arleigh Burke class (from 1991) displacing up to 9,600 tons compared to just 2,200 tons for the Allen M. Sumner class (1943) — a nearly 340% increase. The advent of guided missiles allowed destroyers to take over the surface-combatant roles of battleships and cruisers, making them the global standard for surface combatants in the 21st century, with only the United States and Russia still officially operating heavier cruisers. Modern guided-missile destroyers like the Arleigh Burke class are actually larger and more heavily armed than most WWII-era cruisers, carrying over 90 missiles each, while the Chinese Type 055 is even described as a cruiser in some US Navy reports due to its immense size and armament. However, many NATO navies (such as the French, Spanish, and German) use the term "frigate" for their destroyers, which creates significant confusion in naval terminology.