Milling processing refers to the method of process to cut metal or other material into the desired shape as rotating cutting tools at high speed. It is generally used for machining square objects, and the workpiece is fixed and machined by using a vise or clamping jig. By changing the cutting tools, it is possible to machine flat surfaces, holes, grooves, etc. Also, by using a machining center equipped with NC, it is possible to perform three-dimensional machining of curved surfaces, different shapes, etc., as well as combining processing.