Where does the word carbon copy originate from?

Answer 1

When someone says 'carbon copy' they mean to make a duplicate. This term originated because carbon paper was the item used to make duplicate copies of handwritten or typewritten documents.

Answer 2

The term "carbon copy" originates from the practice of creating duplicate copies of typed or written documents using carbon paper. Carbon paper was placed between the original document and a blank sheet of paper, so that when the original was written or typed on, the pressure transferred the ink or impressions onto the underlying sheet, creating an exact copy. The term "carbon copy" later came to be used metaphorically to mean an exact or identical duplicate of something.