Firstly, milling cutters are generally divided into the following categories: 1. Flat end milling cutter, for precision or rough milling, milling grooves, removing a large amount of blank, small area horizontal plane or contour precision milling; 2. Ball end milling cutter for semi precision milling and precision milling of curved surfaces; A small knife can finely mill small chamfers on steep surfaces/straight walls. 3. Round nose milling cutter, used for rough milling with small surface changes, fewer narrow concave areas, and more relatively flat areas. 4. The flat end milling cutter has chamfers, which can be used for rough milling to remove a large amount of blanks, and can also be used for fine milling of small chamfers on flat surfaces (relative to steep surfaces). 5. Formed milling cutters, including chamfer cutters, T-shaped milling cutters or drum cutters, toothed cutters, and internal R-cutters. 6. Chamfer cutter, which has the same shape as the chamfer and is divided into milling cutters for circular chamfering and oblique chamfering. 7. T-shaped cutter, capable of milling T-shaped grooves; 8. Tooth cutter, milling various tooth shapes, such as gears. 9. Coarse leather cutter, designed for cutting aluminum copper alloy, can be quickly processed There are two common materials for milling cutters: high-speed steel and hard alloy. The latter has higher hardness and stronger cutting force compared to the former, which can increase the speed and feed rate, improve productivity, make the tool less obvious, and process difficult to machine materials such as stainless steel/titanium alloy. However, the cost is higher, and the tool is easy to break when the cutting force changes rapidly. From the above content, it is clear that a flat bottom milling cutter is actually a type of end milling cutter. There are many types of milling cutter shapes, such as ordinary milling machines and CNC milling machines, which are used to process grooves and linear contours, as well as machining cavities, cores, and surface shapes/contours on milling and boring machining centers.