There are many uses for using the file on the Swiss Army knife. One of which is probably to file your nails which is probably what most people think its for. The file can be used in woodwork to get something to be smoother than it is. Strangely it can also be used to open a letter. This specific tool, the file does not have that many uses I could list here but whenever the occasion rises one does now and then find a use for it. The file has another use I did not mention. With the file you can saw off small screws and bolts as well.