Turrets are interesting items. They can serve different functions, but may also be used as an element of style. The two different kinds of turrets that most people are familiar with are the architectural turret and the mechanical turret.
In the architectural sense, a turret is similar to a small tower, but differs in that is raised from the structure itself rather than from the ground. It may be referred to as a hanging turret, and is usually placed on the corner of a structure. Turrets often have a pointed or conical roof and are sometimes quite ornamental. They are often found in castles, palaces, medieval style buildings and homes, and fortresses. The Queen Ann style still uses turrets, and turrets are sometimes found in theme buildings, such as restaurants made to look like castles or structures for Renaissance fairs.
A turret may be used simply to create a grander style, or it may be a functional element such as a lookout point for a fort, situated high above the main body of the structure. Turrets are generally narrow and may contain spiraling staircases. In some stories and fairy tales, a turret is used as an area to keep someone captive, to spy on other kingdoms, or to watch for approaching enemies.
In the mechanical sense, turrets have many different uses, but are usually noted for their ability to pivot or rotate. Turrets may be simple pieces added to equipment to hold tools, which can be rotated to keep specific implements within reach. Microscopes also contain turrets, which are basically plates that move in order to offer different levels of magnification.
Probably the most well known types of mechanical turrets are gun turrets. While a lookout in a fort that contains weapons may also be called a gun turret, the mechanical type is noted for its ability to rotate. Think of tanks with gun turrets that pivot in every direction with a gun protruding from a small opening. This type of turret allows a tank operator to view and protect from all sides.