The printers are the primary output devices, which are used to prepare permanent documents of output, called hard copy of output. It is one of the most conventional and useful methods for delivering information using printed characters. The types of printers can be classified on the basis of two distinct methods of producing print:
• Impact printers: The printers, which print through striking the characters against the ink pads or ribbons so that the impressions are printed on the paper, are known as impact printers. These printers have a mechanical contact between the printer head and paper, such as line printer and character printer.
• Non impact printers: The printers, which print using laser, magnetic or thermal technology, are known as non impact printers such as electromagnetic printers, thermal printers, desk jet printers and laser printers.