A printer is one of the output devices of a computer, used to print the results of computer processing onto relevant media. There are three indicators to measure the quality of a printer: print resolution, print speed, and noise. There are many types of printers, classified into impact printers and non impact printers based on whether the printing element has a striking action on the paper. According to the printing character structure, it can be divided into full form character printers and dot matrix character printers. Divided into string printers and line printers by forming a line of characters on paper. According to the technology used, printers can be classified into cylindrical, spherical, inkjet, thermal, laser, electrostatic, magnetic, LED, and other types.

The printer was co invented by John Walter and Dave Donald. A device that prints the results of computer operations or intermediate results on paper in a format that humans can recognize, such as numbers, letters, symbols, and graphics. Printers are developing towards lightweight, thin, short, small, low-power, high-speed, and intelligent directions.

With the rapid development of the Internet, some people predict that the paperless era is coming, and the end of printers has arrived. However, global paper consumption is growing exponentially every year, and printer sales are increasing at an average rate of nearly 8%. All of this indicates that printers will not only not disappear, but will also develop faster and have a wider range of applications.

The basic working principle of inkjet printers is to first generate small ink droplets, and then use the inkjet head to guide the small ink droplets to the set position. The smaller the ink droplets, the clearer the printed image. The basic principle may seem simple, but it's not that easy to operate. Just as the principles of calculus are not complicated, what is complex is how to apply them.