The word file has several meanings:

1. A container or folder for organizing papers and documents. Teachers keep student work in files, and offices use filing cabinets with drawers full of files to store important records. When you file something away, you put it in its proper place so you can find it later. Computer files work the same way: they store information digitally, whether it's a document, a photo, or a program.
2. A metal tool with a rough surface used for smoothing or shaping materials. A carpenter might use a file to smooth the edge of a wooden board, while someone might file their fingernails to make them even. The tool works by scraping away tiny bits of material with each stroke.
3. To walk in a line, one behind the other. After a fire drill, students file back into school in an orderly way. When people file out of an auditorium after an assembly, they exit in a steady stream, following the person ahead.
4. To officially submit a document or make a formal request. A business might file taxes with the government, or someone might file a complaint about poor service. Filing paperwork means turning it in to the right office or authority.