A cruiser is a high-speed, comparatively lightly armed warship. Originally the term cruiser was applied to privateers, fast armed ships which preyed upon merchant shipping in the 17th and 18th centuries.
At the end of the 19th century, a class of war-vessels intended to possess a high rate of speed, and also no small degree of fighting-power, but less than what belonged to the battleship was developed and called Cruisers. Their special purpose was that of protecting merchant vessels, scouting, etc - such work as formerly was performed by frigates or corvettes. There were several sizes and types of British cruisers at the end of the 19th century and start of the 20th century, some of them being 'armoured', while a much larger number were only 'protected'. The former had an armourbelt of considerable thickness, while the latter had only deck armour. The former were mostly of the later construction than the latter, and were of greater speed - from 22 to 24 knots or more per hour. Research Cruiser
Abbreviations
Ships
Research Cruiser