In the context of metalworking, a cutting tool, is any tool that is used to remove metal from the workpiece by means of shear deformation. It frequently refers to as a tool bit. In order to perform a long time, cutting tools must be made of a material harder than the material which is to be cut, and the tool must be able to withstand the heat generated in the metal cutting process. Also, the tool must have a specific geometry, designed so that the cutting edge can contact the workpiece without the rest of the tool dragging on the surface of the piece part surface. The angle of the cutting face is also important as is the flute width, tool margin and tool material.

In practice, there are a range of materials used as cutting tools. These include stainless steel and steel types such as martensitic stainless steel and austenitic stainless steel, low carbon steel, free machining steel, medium and high plain carbon alloy and tool steel and ferritic. Some of the more higher-end tools include heat-resistant super alloys and titanium types like iron-based, cobalt-based, and nickel-based alloys, titanium and titanium alloys.