We just learned how a Metal Lathe is a piece of metal being spun around while a sharp tool cuts it.
Another type of tool for cutting metal is a Mill.
A mill is a machine that has a tool that spins around very fast, while the piece of metal you want to cut is being held still.
So in a way it's the opposite of a lathe, where the metal is spinning and the tool is held still.
(from: wikipedia - milling (machining))
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