milling machine-2

Milling is the machining process of using rotary cutters to remove material
Milling is a cutting process that uses a milling cutter to remove material from the surface of a workpiece.
It is one of the most commonly used processes in industry and machine shops today for machining parts to precise sizes and shapes.
The milling cutter is a rotary cutting tool, often with multiple cutting points.

Reference from: wikipedia