Cruiser

A cruiser is a type of warship. The term has been in use for several hundred years, and has had different meanings throughout this period. During the Age of Sail, the term cruising referred to certain kinds of missions – independent scouting, commerce protection, or raiding – fulfilled by a frigate or sloop, which were the cruising warships of a fleet.

In the middle of the 19th century, cruiser came to be a classification for the ships intended for cruising distant waters, commerce raiding, and scouting for the battle fleet. Cruisers came in a wide variety of sizes, from the medium-sized protected cruiser to large armored cruisers that were nearly as big (although not as powerful or as well-armored) as a pre-dreadnought battleship. With the advent of the dreadnought battleship before World War I, the armored cruiser evolved into a vessel of similar scale known as the battlecruiser. The very large battlecruisers of the World War I era that succeeded armored cruisers were now classified, along with dreadnought battleships, as capital ships.

By the early 20th century after World War I, the direct successors to protected cruisers could be placed on a consistent scale of warship size, smaller than a battleship but larger than a destroyer. In 1922, the Washington Naval Treaty placed a formal limit on these cruisers, which were defined as warships of up to 10,000 tons displacement carrying guns no larger than 8 inches in calibre; heavy cruisers had 8 inch guns while those with guns of 6.1-inches or less were light cruisers, which shaped cruiser design until the end of World War II. Some variations on the Treaty cruiser design included the German Deutschland class "pocket battleships" which had heavier armament at the expense of speed compared to standard heavy cruisers, and the US Alaska class which was a scaled-up heavy cruiser design designated as a "cruiser-killer".

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