While considerably more complex and expensive than most other common printer types, laser printers are capable of producing extremely high-quality text and graphics (including color) at fantastic speeds. At their most basic, laser printers apply an electrostatic charge to a drum inside the printer cartridge.
A laser or a light-emitting diode then discharges portions of the drum to form the characters or graphics. Charged toner attaches itself to these discharged sections. A charged piece of paper is passed over the drum, transferring the toner. The toner is heated and fused to the sheet.