Carbon paper
Carbon paper is a special kind of paper that can be used for copying. On one side, the paper is coated with dry ink, which is usually bound with a kind of wax. It is usually put between two sheets of paper. When pressure is applied from the first sheet, some ink is transferred to the second one.The copy that is produced that way is called carbon copy. Because it relies on pressure, the technique is limited to only four or five copies.