After the advent of computer numerical control (CNC) in the 1960s, milling machines evolved into machining centers: milling machines augmented by automatic tool changers, tool magazines or carousels, CNC capability, coolant systems, and enclosures. The original class of machine tools for milling was the milling machine (often called a mill). Milling can be done with a wide range of machine tools. It is one of the most commonly used processes for machining custom parts to precise tolerances. Milling covers a wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. This may be done by varying directions on one or several axes, cutter head speed, and pressure. Milling is the process of machining using rotary cutters to remove material by advancing a cutter into a workpiece.
A 3-axis clone of a Bridgeport-style vertical milling machine For asphalt milling machines, see Pavement milling.
