Both lathes and milling machines are used to remove material from a workpiece. Lathes, however, involve rotating a workpiece against a single-bladed cutting tool, whereas milling machines involve rotating a multi-bladed or -pointed cutting tool against a stationary workpiece.

A milling machine removes material from a work piece by rotating a cutting tool (cutter) and moving it into the work piece. Milling machines, either vertical or hori- zontal, are usually used to machine flat and irregularly shaped surfaces and can be used to drill, bore, and cut gears, threads, and slots.

A mill is a device, often a structure, machine or kitchen appliance, that breaks solid materials into smaller pieces by grinding, crushing, or cutting. Such comminution is an important unit operation in many processes. There are many different types of mills and many types of materials processed in them.

mini·​mill ˈmi-nē-ˌmil. : a relatively small-scale steel mill that uses scrap metal as starting material.