A turret is a tiny tower that is either built on top of another tower or affixed to the side or corner of a building. They can be round, square, hexagonal, octagonal, or any other shape that results in a narrow tower-like structure that is attached to or a part of the main structure. The word comes from the Turkish turretti, meaning "little church". In medieval Europe, they were often built as defensive structures with no religious function, but rather to give warning of an enemy attack. Today, they are most often found in historical buildings or museums that need to be protected from damage caused by weather or visitors. A turret room is a small room located on the top floor or attic of a building. These rooms provide views over much of the city for those living or working up there, and sometimes allow for additional storage space. Because of their location, they are usually less expensive than equivalent rooms on other floors, if not free. In modern buildings, these rooms may be used for office space, or even as housing. In historic buildings, they often contain only a bed and a chest for storage, but they are still useful places to sleep during periods when it isn't necessary to remain in one place. Some people like to take tours of cities at night, looking for signs of life in locations where others cannot see them.