Automatic carriers (also called turret or tool changer) are machine tools used in the metalworking industry to machine the workpiece. The automatic tool carrier makes it possible to use several tools in one machine to perform different machining steps without having to manually change over the workpiece. The automatic tool carrier is usually a rotating tool head that can hold multiple tools. The tools are automatically selected and positioned to machine the workpiece. The advantage of automatic carriers is that they allow complex machining operations to be performed automatically and increase productivity. There are several types of automatic carriers, including horizontal and vertical designs. Horizontal-automatic lathes have a horizontal headstock and are designed for machining longer workpieces. Vertical-automatic lathes have a vertical headstock and are suitable for machining shorter workpieces. Most modern automatic lathes are computer controlled and can be programmable to perform a variety of machining operations, including turning, milling, drilling, tapping and more.