Carbon paper is a thin sheet coated with a layer of carbon or other ink on one side. It is used to create copies of handwritten or typed documents by placing it between two sheets of paper. When pressure is applied, such as when writing or typing, the carbon transfers onto the bottom sheet, producing a duplicate. Originally popular before the digital age, carbon paper was widely used in offices and homes for making copies of important documents. Although its use has declined with the advent of photocopying and scanning technologies, it remains a simple and effective tool for creating duplicates without electricity.