Knee-and-column milling machines, also called variable-speed vertical milling machines, use rotary cutting tools to remove material from a workpiece. The cutting tools are held in a vertical orientation and the workpiece is secured in a horizontal orientation on the machine's table. The table can be raised and lowered for making plunge cuts. Vertical milling machines are typically simpler to operate and take up less space than horizontal milling machines. Milling machines are used in manufacturing plants and machine shops to create parts with complex shapes and features.