Grinding is a machining process that takes a very light “cut” using abrasive media—typically an abrasive grinding wheel. Grinding wheels with different grit sizes achieve rougher or finer grinding passes, according to the needs of the application. When precise accuracy and/or surface finish are required, grinding is often used as a finishing process after some other metalworking operation. Grinding is also an effective process for machining workpiece materials that are too hard for milling or turning. Some grinders machine round parts. These machines include cylindrical grinders and centerless grinders. Some grind flat surfaces. These are surface grinders. Form grinders move the work and/or the wheel in various axes to grind surfaces that are precisely contoured. Still other grinders are dedicated solely to machining the hard materials necessary to produce cutting tools for other types of machining operations. These are referred to as tool grinders or cutter grinders.