Tools can be divided into five categories according to the form of the workpiece machining surface:

Tools for machining

various external surfaces, including turning tools, planers, milling cutters, outer surface broaches and files, etc.: hole machining tools, including drills, reaming drills, bracing tools, cutting tools and inner surface broaches, etc.;

Thread processing tools, including wire push, plate teeth, automatic opening and closing thread cutting heads, thread turning tools and thread milling cutters, etc.;

Gear processing tools

, including hobs, gear shaping cutters, shaving cutters, push gear processing tools, etc.;

Cutting tools,

including toothed circular saw blades, band saws, bow saws, cutting turning tools and saw blade milling cutters, etc. In addition, there are combination tools.

According to the cutting movement mode and the corresponding cutting edge shape, the tool can be divided into three categories:

General tools, such as turning tools, planing cutters, milling

cutters excluding forming turning tools, forming roe deer planers and forming milling cutters), boring cutters, drills, reaming drills, comparison knives and saws, etc.;

Forming tools, the cutting edge of such tools

has the same or nearly the same shape as the section of the workpiece to be machined, such as forming turning tools, forming spores planing cutters, forming milling cutters, broaching tools, conical reamers and various threading tools;

Expansion tool is the tooth surface of the gear or similar workpiece processed by the development method, such as hob, gear shaping cutter, shaving cutter, push gear foaming cutter and bevel gear milling cutter.