Printers are terminal equipment or peripheral devices of computers that reproduce text and graphics in a readable or interpretable form on paper or a similar visualization medium. In addition, there are printers with which three-dimensional bodies can be printed, the 3D printers.
Printers can produce the print image mechanically, by mechanical impact via needles or type levers on ink or carbon ribbons, which transfer the print image to the medium. Such printers are called impact printers. They include dot matrix printers, type wheel printers, line printers, steel belt printers and ball head printers. Impact printers use hammers to press fonts or needles against the ink ribbon, which delivers the ink to the paper or other supporting medium. Impact printers are bound to a predetermined print and typeface.
Non-impact printers, on the other hand, operate without impact and do not exert any mechanical pressure. With these printers, the print image is generated electronically by dots, lines or pages and applied to the paper by thermal, electrostatic or optical processes. Non-impact printers include inkjet printers, thermal printers, laser printers, mini photo printers such as thermoautochrome printers or ZINK, which stands for Zero Ink, and LED printers, which are also used in multifunction devices; special printers with non-impact processes include plastic card printers. Unlike other printers that work with the CMYK color model, card printers work with the Yellow, Magenta, Cyan, Key, Overcoat(YMCKO) color sequence. Non-impact printers can print any typeface, as well as graphic and photographic prints.
Distinguishing features of printers
Important distinguishing features of printers are printing speed, resolution, printer memory, single and multi-color printing, and noise. In addition, the printer interface, printer control languages and printable fonts.
As for the printing speed, it is influenced by various factors such as the host computer, the printer driver, the printer interface and the printer 's processing power. Likewise by the type of printing, whether black and white or color printing, the number of printed pages and the print resolution. In order to be able to achieve comparability in the values, the ISO has specified test procedures with different print files, paper types and printing technologies in its ISO/ IEC 24734 standard. If you measure it in terms of size, the values for simple printers can be as low as 10 pages per minute, while high- performance printers can print over 100 pages per minute.
In addition to the listed printers that produce a two-dimensional print image, there are also 3D printers that can print three-dimensional bodies.