Printers that include non-printing features are sometimes called multifunction printers (MFP), multi-function devices (MFD), or all-in-one (AIO) printers. Local printers are also increasingly taking over the process of photofinishing as digital photo printers become commonplace. Printers are routinely classified by the printer technology they employ; numerous such technologies have been developed over the years. Solid ink printers, also known as phase-change printers, are a type of thermal transfer printer. Solid ink printers are most commonly used as colour office printers, and are excellent at printing on transparencies and other non-porous media. Solid ink printers can produce excellent results. Acquisition and operating costs are similar to laser printers. Previously, solid ink printers were manufactured by Tektronix, but Tek sold the printing business to Xerox in 2001 A dye-sublimation printer (or dye-sub printer) is a printer which employs a printing process that uses heat to transfer dye to a medium such as a plastic card, paper or canvas. While once the province of high-end print shops, dye-sublimation printers are now increasingly used as dedicated consumer photo printers. The impact printer uses a print head that hits the surface of the ink ribbon, which presses the ink onto the paper. All but the dot matrix printer rely on the use of formed characters, letterforms that represent each of the characters that the printer was capable of printing. Impact printers varieties include, typewriter-derived printers, teletypewriter-derived printers, daisy wheel printers, dot matrix printers and line printers.
Ballistic wire printers (discussed in the dot matrix printers article)
Stored energy printers
24-pin print heads were able to print at a higher quality. Once the price of inkjet printers dropped to the point where they were competitive with dot matrix printers, dot matrix printers began to fall out of favor for general use.
Some dot matrix printers, such as the NEC P6300, can be upgraded to print in colour. Colour graphics are generally printed in four passes at standard resolution, thus slowing down printing considerably. Dot-matrix printers are now (as of 2005) rapidly being superseded even as receipt printers.Line printers, as the name implies, print an entire line of text at a time. In drum printers, a drum carries the entire character set of the printer repeated in each column that is to be printed. In chain printers, also known as train printers, the character set is arranged multiple times around a chain that travels horizontally past the print line. Comb printers, also called line matrix printers, represent the third major design. These printers were a hybrid of dot matrix printing and line printing. Because far less motion was involved than in a conventional dot matrix printer, these printers were very fast compared to dot matrix printers and were competitive in speed with formed-character line printers while also being able to print dot matrix graphics.
Line printers were the fastest of all impact printers and were used for bulk printing in large computer centres.