What is a printer


While printers were very expensive in the early days of personal computers, cheap and good quality printers are no longer a luxury today. As a rule, every computer owner has a printer. In the private sector, inkjet printers are mainly sold. Their consumables (color cartridges and special paper) are, however, comparatively expensive. However, the acquisition costs for the device are low. A laser printer is more likely to be used as an office printer. The printout is usually of higher quality.
Basically you can say that cheap printers result in enormous follow-up costs if you print a lot. That's why most printer buyers have noticed that the prices for cartridges are almost so high that you can buy a new printer for them. This shows that the purchase of a printer is financed by purchasing accessories. Stupid for those who use their printer a lot.

Printer types

  • Type wheel printer
  • Thermal printer
  • Thermal transfer printer
  • Dye sublimation printer
  • Dot matrix printer
  • Inkjet printer
  • Laser printer
  • LED printer
  • Multifunction printer

Except for dot matrix printers, inkjet printers and laser printers, all other types of printer do not play a role in the computer sector.

Comparison of printer types

Type wheel printergood typeface, document-proofloud, slow, no graphics
Dot matrix printersuitable for copiesbad typeface, loud, slow
Inkjet printercheap devices, photo qualityno breakdown, light and color sensitive
Laser printervery good typeface, indelibleexpensive, no breakdown, environmental pollution from ozone

Type wheel printer

The type wheel or ball head on which all printable numbers, letters and characters are stamped is located in the type wheel printer. A type wheel printer can only print numbers, letters, and punctuation marks.
If a letter is to be printed, a motor turns the type wheel until the letter is placed in front of a hammer. The hammer then strikes the letter on a ribbon. The letter is pressed onto the paper.
Due to the extensive and heavy mechanics, this printing process only allows a few characters per second. The print image is comparable to that of a typewriter.

Dot matrix printer

A needle printer has a print head that consists of several needles. There are printheads with 9, 24 and 48 pins. Black and white dot matrix printers usually have 9 needles. Color printer 24 needles. Because of the clearly sharper print image of inkjet printers and laser printers, dot matrix printers with 48 needles have not caught on.
With the 9-pin printer, the pins are in a row one below the other. With 24-needle printers, they are arranged in two rows of 12 needles each one below the other.
A dot matrix printer is addressed differently depending on the application program and printout. Either the needles are controlled by a bit code, with the printer printing the letter independently. Graphics are sent to the dot matrix printer in individual bit structures. This printing process prints 150 to 400 characters per second.
The big disadvantage of dot matrix printers is the noise they make when printing. The mechanism that hurls the needles through the ribbon onto the paper creates a high level of noise. Cover hoods reduce this noise when printing.
Although this printing method is basically out of date, these printers are still used in industrial companies. Here the continuous paper feed and the creation of a carbon copy have advantages.

Inkjet printer

Inkjet printers are powerful and inexpensive standard printers. They work in a similar way to dot matrix printers. Instead of needles, liquid wax, a type of ink, is sprayed onto the paper. The printing technology is so good that it practically achieves photo quality. Because large-area prints on normal paper cause the paper to ripple, special paper is necessary for photo prints. However, the printout is not document-proof and sensitive to moisture and permanent UV light.

Laser printer

Laser printers work similarly to photocopiers. The printout generated is document-proof, smudge-proof and has a razor-sharp print image. The printing process takes place completely without a stroke with 6 to 25 pages per minute.
The print image is applied line by line to an image drum with a laser beam. The toner adheres to the charged areas of the image drum and is then applied to the paper and fixed with heat. This creates a perfect print quality.
As a rule, the purchase price is higher than that of inkjet printers. The devices are larger and emit odors (e.g. ozone). The location of a laser printer should therefore be well ventilated. Cheap laser printers are only available as monochrome laser printers. Color laser printers and the color toner are a lot more expensive.

LED printer

LED printers are similar to laser printers. Because with LED printers, toner is also used. The print quality is comparable to that of laser printers.
Instead of a laser beam, the exposure unit is exposed to light-emitting diodes (LEDs). An LED bar brings light to the light-sensitive image drum. The coating of the imaging drum is electrostatically negatively charged. The charge is released where the light hits the imaging drum. Then the imaging drum rotates past the toner storage area and attracts the toner particles to the places where the light fell. Then the drum rotates past the paper. The toner is transferred to the paper. The fuser unit heats and presses the toner onto the paper, which keeps the toner fixed to the paper.

Multifunction devices (MFG) / multifunction printer (MFD)

Multifunction devices (MFG) or multifunction printers (MFD) are printers that are additionally equipped with a flatbed scanner, fax and copier function. The multifunctional device only consists of a printer, scanner and modem. A microprocessor system interconnects the individual parts to form functional units. This turns the scanner and printer into a photocopier. The scanner and modem are used to send faxes. And the printer and modem are used to receive faxes. Printers and scanners also work on their own. The printing unit is usually an inkjet printer. But there are also multifunctional devices with laser printers.
The individual components are not always of the same quality. As a rule, the built-in scanner is inferior to normal cheap flatbed scanners. As a general rule, it can be assumed that the printer is the only part of the All-In-One that works best.
Another advantage of multifunctional devices is the small footprint compared to all individual devices. A multifunction device usually replaces a stand-alone scanner, fax machine and copier.


The resolution of a printer is given in DPI. This is the abbreviation for dots per inch. The resolution is only a theoretical value that does not say anything about the actual level of detail of a printer. Stripes, false colors, artifacts and blurring in the printout are still to be expected.
The DPI indication should never serve as a purchase argument.


Regardless of the device purchase price, you should also look at the prices for ink cartridges, toner cartridges and special paper. Of course, you can also get cheaper prices from an alternative provider, provided the printer has been on the market for a few months.
Before buying a printer, it is worth taking a look at the retailer's accessories and consumables area. It should be noted that the cheaper a printer, the more expensive the ink or toner cartridges are.
When buying a printer, it is advisable to rely on a manufacturer for whom there is a wide range of alternative inks and toners. Because this keeps the price for the original accessories within reasonable limits.

Printer interfaces

Printers are connected to the computer either via the parallel interface (Centronics) or via USB. The USB port is sufficient as a printer for a single user. In offices where several people operate a printer, a network interface is an advantage.


A special feature is the USB interface with PictBridge support. A digital camera can be connected here, which must also support PictBridge. Pictbridge emerged from the Direct Print Standard. The manufacturers Canon, Fuji, Hewlett Packard, Olympus, Seiko and Sony have developed it to connect digital cameras to a printer directly via USB and in this way to print out images from the digital camera on the printer without a computer. The selection of images and the print commands are controlled via the display of the digital camera. Some printers even have a small display, which makes it easier to operate the printer and select images.

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