A file is a tool used to remove fine amounts of material from a workpiece. It is common in woodworking, metalworking, and other similar trade and hobby tasks. Most are hand tools, made of a case hardened steel bar of rectangular, square, triangular, or round cross-section, with one or more surfaces cut with sharp, generally parallel teeth. A narrow, pointed tang is common at one end, to which a handle may be fitted.[1]

A rasp is a form of file with distinct, individually cut teeth used for coarsely removing large amounts of material.[2]

Files have also been developed with abrasive surfaces, such as natural or synthetic diamond grains or silicon carbide, allowing removal of material that would dull or resist steel files, such as ceramic.

There are various types of industrial files that are designed for specific applications :

1. Flat file: A flat file is a general-purpose file that is used for smoothing, shaping, and removing material from flat surfaces.
2. Round file: A round file is used for enlarging round holes and shaping curves or contours.
3. Half-round file: A half-round file is used for smoothing and shaping concave and convex surfaces.
4. Triangular file: A triangular file is used for filing sharp corners and angles.
5. Square file: A square file is used for filing slots, keyways, and internal angles.
6. Knife file: A knife file is a narrow file with a tapered tip, used for cutting and sharpening.
7. Crossing file: A crossing file has a diagonal pattern of teeth and is used for filing in a crosshatch pattern.
8. Rasp file: A rasp file has coarse teeth that are used for rapid material removal on wood or soft materials.
9. Needle file: A needle file is a small, precision file with a fine point that is used for intricate work, such as working with jewelry or electronics.

The type of industrial file chosen will depend on the specific task at hand and the material being worked on. Choosing the right file is crucial to ensure efficient and accurate work.