A printer is one of the output devices of a computer, and is used to print the results of computer processing on related media. There are three indicators to measure the quality of a printer: print resolution, print speed and noise. There are many types of printers. According to whether the printing element has a striking action on the paper, it is divided into impact printers and non-impact printers. According to the structure of printing characters, it is divided into full-shaped character printers and dot-matrix character printers. According to the way a line of words is formed on paper, there are serial printers and line printers. According to the technology used, it is divided into cylindrical, spherical, inkjet, thermal, laser, electrostatic, magnetic, light-emitting diode and other printers.
