Both grinding and milling remove material physically from a workpiece. Grinding is a process of removing material from the workpiece utilizing a wheel with an abrasive surface. On the other hand, milling is a process of removing material from the workpiece with the help of different cutters rotating in a direction perpendicular to the axis of the workpiece.

CNC is abbreviated as Computerised Numerical Control. VMC is abbreviated as Vertical Machining Centre.

CNC milling machines are used to cut metal and wood with precision and accuracy. Yet, the number of items and components that may be produced with a CNC milling machine is virtually endless, as the machine is capable of cutting a huge array of shapes and angles.

There are numerous types of milling machines. Some of them can be stated here: Column and knee type, Plain or horizontal, Vertical, Universal, fixed bed type, Simplex, Duplex, Triplex, Planer type, Rotary table, Drum type, Profile milling, Planetary type, Tracer controlled, Pantograph type, and CNC milling machine.

The workpiece is set up on the table. Arbour is adjusted with the cutting tool. The knee position is adjusted along with the table position. Cutting action is completed by feeding the workpiece against a rotating cutter. Finally, the workpiece is removed.