A standard wooden pencil is a tool for writing. The outside of the pencil is wood. This wood is often yellow. Inside the wood is a long, thin piece of graphite. The graphite is black and it makes marks on paper. At the top of the pencil, there is a small metal part. This metal part is called a ferrule. The ferrule holds the eraser. The eraser is usually pink. People use the eraser to remove pencil marks. Pencils are common tools in schools and offices around the world.