A nail file is a small tool used to shape and smooth the edges of fingernails and toenails. It typically consists of a flat piece of material, often coated with an abrasive surface, which helps to gently grind down the nail's surface. Nail files come in various materials, including emery board, glass, and metal, each offering different levels of coarseness for specific nail care needs. Using a nail file is a simple process. To file nails, one should hold the file at a slight angle and move it in one direction, avoiding a back-and-forth motion that can cause splitting. Regular use of a nail file can help maintain healthy nails and enhance their appearance.