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. Grinders for round parts include cylindrical and centerless grinders. Grinders for flat surfaces are called surface grinders. Form grinders move the work and/or the wheel in various axes to grind surfaces that are precisely contoured. Grinders used to create and sharpen cutting tools are called tool & cutter grinders.