What is the purpose of a file in shop work?

A file is a hand tool with a ridged, abrasive surface used to smooth rough edges, shape material, deburr, or remove small amounts of metal, wood, or plastic. Files come in many shapes (flat, round, half-round, triangular) and cuts (coarse to fine) for different jobs. They are pushed across the workpiece in one direction for best results. A file removes material gradually and with control, unlike a saw (which cuts through) or a plane (which shaves wood). Recognizing the file as a smoothing and shaping tool is standard hand-tool content on the Shop subtest.