CNC machine shops have become very popular nowadays as they have improved the quality of machine parts by automating many of the repetitive processes involved in making custom parts. CNC may be applied to a wide range of machining operations including Laser Cutting, CNC Vacuum Forming, CNC Turning and CNC Water Jet Cutting in addition to the CNC Milling process.  The selecting the right CNC process depends upon the type of material and its physical properties on the one hand, and on cost and speed on the other.

For example, laser cutting works well on materials such as high and low carbon steels and stainless steel, but its effectiveness in cutting of aluminum or copper alloys is much lower due to reflectivity or heat conduction. So, other procedures should be applied on these types of material. Most of the major cutting procedures may be run in the CNC environment which eMachineShop make available via the internet through proprietary software design application.

CNC is short for "computer numerical control" and is required to run manufacturing machines. The CNC machines are run by programmed software and it possesses certain features which manufacturers of major milling, turning, and cutting machines have integrated for the CNC machine shop. Various shapes for different parts can be easily formed with CNC machines like pointed one, 2D or 3D shapes. These shapes can be formed on even stiff materials and this process also proves economical for making several pieces of similar dimension in one setup. These manufacturing machines can be controlled to within a small fraction of an inch (a few 10-thousandth's of an inch is possible) with CNC software system. The CNC machining is of immense help for the mechanical industries as it can provide flexibility to manufacture machine parts of various intricate design and shape while holding extremely close tolerances which would tax even the most proficient of human machinists when done repetitively for hours on end.

Previously, the traditional machines were not so advanced in producing the machinery part and they often faced the problem in designing intricate machine parts. But, when CNC came in to the field, the customized machine parts are produced with great precision with the help of the computer updated software system, which are installed to work in the CNC machine shop. NC technique hardware was the first to use CNC machines. In the year 1940 and 1950, a laboratory was opened with the collaboration of MIT Servomechanisms Laboratory by John. T. Parsons. With the launch of CNC machining, a drastic change has taken place in the mechanized and engineering commerce. Every work of the machinery is now performed through CNC machining in CNC machine shop. The automation process in the engineering industry has improved a lot and the researches are going on to discover new applications and new vistas of CNC machining.

Some machines can produce one thousand pieces simultaneously and sometimes no operator or checking sensors are required. The movement of the machines depends totally on the software programming and sometimes they move in a perpendicular form or sometimes in a circular form.