Machining is any one of a number of various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process. The many processes that have this common theme, controlled material removal, are today collectively known as subtractive manufacturing, in distinction from processes of controlled material addition, which are known as additive manufacturing.
Exactly what the "controlled" part of the definition implies can vary, but it almost always implies the use of machine tools (in addition to just power tools and hand tools).
Much of modern day machining is carried out by computer numerical control (CNC), in which computers are used to control the movement and operation of the mills, lathes, and other cutting machines. The equipment in our facility ranges from CNC converted Brown and Sharpe Screw Machines, Fixed Head Stock Lathes, Citizen Swiss machining centers and powerful Vertical and Horizontal machining centers. Complete list available upon request.