Coated Stock is paper with any kind of coating that improves reflectivity and ink that is applied after the paper is made to provide a smooth finish. The most common coating options are gloss, matte, satin, dull.
C1S: An abbreviation for “Coated One Side,” which means the paper is only coated with a protective gloss, matte or finish on one side of the sheet.
C2S: An abbreviation for “Coated Two Sides,” which means the paper is coated with a protective gloss, matte or finish on both sides of the sheet.
Uncoated Stock is paper that does not have a coating of any kind.