The platen is the cylinder in an impact printer (such as a |dot-matrix| or daisy wheel printer) around which the paper wraps. As the cylinder turns, the paper is brought past the print head. The print head strikes the ribbon against the paper, using the platen as a backstop. The platen usually is covered by a semi-soft rubbery material to minimize risk of damage to the print head mechanism or the paper. The platen may be advanced manually by turning a platen roller. This is a knob on the end of the cylinder.
