An eraser, or a rubber, is a tool made from rubber that is used to get rid of marks made from a pencil, or some types of pen. Another kind of eraser is made of felt and is used to remove chalk marks from a blackboard. Some may also be automatically be attached to a pencil, or could be bought to be shoved on a top of a pencil. Erasers can be used by rubbing the mistake and it will slowly clear away. All erasers will produce some dust called debris after rubbing and it will usually be black as it cleared away the pencil marks. Some erasers produce a lot of dust while some produce dust that all stick together. There are some good-quality erasers which are very soft and can erase easily, while some are very hard, and a lot of rubbing is needed. The classic pink eraser is made for smaller, lighter errors, whereas a thick, white eraser is made for bigger and/or darker marks.