Kind of Printer

COMPUTER INPUT / OUTPUT

Any computer system comprises three stages: input-process-output. That's true of every application, from games and the Internet to Word Processing and databases. In this section you can learn about how the various devices used to facilitate basic PC input and output.

Input Devices

The keyboard and mouse are essential peripherals, but there are many methods for inputting to the computer depending on the application.

Kind Of Printer

Laser Printers

Laser printing is fast and clean, and has even become competitive in its pricing. Learn how it works.

In the 1980s, dot-matrix and laser printers were pre-dominant, with inkjet technology not emerging in any significant way until the 1990s. The laser printer was introduced by Hewlett-Packard in 1984, based on technology developed by Canon. It worked in a similar way to a photocopier, the difference being the light source. With a photocopier a page is scanned with a bright light, while with a laser printer the light source is, n

ot surprisingly, a laser. After that the process is much the same, with the light creating an electrostatic image of the page onto a charged photoreceptor, which in turn attracts toner in the sh

ape of an electrostatic charge.

Laser printers quickly became popular du

e to the high quality of their print and their relatively low running costs. As the market for lasers has developed, competition between manufacturers has become increasingly fierce, especially in the production of budget models. Prices have gone down and down as manufacturers have found new ways of cutting costs. Output quality has improved, with 600dpi resolution becoming more standard, and build has b

ecome smaller, making them more suited to home use.

Laser printers

have a number of advantages over the rival inkjet technology. They produce much better quality black text documents than inkjets, and they tend to be designed more for the long haul - that is, they turn out more pages per month at a lower cost per page than inkjets. So, if it's an office workhorse that's required, the laser printer may be the best option. Another factor of importance to both the home and business user is the handling of envelopes, card and other non-regular media, where lasers once again have the edge

over inkjets.

Inkjet Printers

Canon are credited with the invention of the inkjet. Now, it's a widely used printer technology, but is it efficient?

Although inkjets were available in the 1980s, it was only in the 1990s that prices dropped enough to bring the technology to the high street. Canon claims to have invented what it terms "bubble jet" technology in 1977, when a researcher accidentally touched an ink-filled syringe with a hot soldering iron. The heat forced a drop of ink out of the needle and so began

the development of a new printing method.

Inkjet printers have made rapid technological advances in recent years. The three-colour printer has been around for several years now and has succeeded in making

colour inkjet printing an affordable option; but as the superior four-colour model became cheaper to produce, the swappable cartridge model was gradually phased out.

Traditionally, inkjets have had one massive attraction over laser printers; their ability to produce colour, and that is what makes

them so popular with home users. Since the late 1990s, when the price of colour laser printers began to reach levels which made them viable for home users, this advantage has been less definitive. However, in that time the development of inkjets capable of photographic-quality output has done much to help them retain their advantage in the realm of colour.

The down side is that although inkjets are generally cheaper to buy than lasers, they are more expensive to maintain

. Cartridges need to be changed more frequently and the special coated paper required to produce high-quality output is very expensive. When it comes to comparing the cost per page, inkjets work out about ten times more expensive than laser printers.

Since the invention of the inkjet, colour printing has become immensely

popular. Research in inkjet technology is making continual advances, with each new product on the market showing improvements in performance, usability, and output quality. As the process of refinement continues, so the price of an inkjet printers continue to fall.

Dot-matrix Printer

Of all the printer types, this is the oldest type. Inspired from typewriter, this printer operates by having its pin strike against the ink ribbon. The print out from dot matrix is easily recognized because of the obvious lines and dots that you can see on the image or character it prints; hence it is called dot-matrix. Despite its obsolescence, dot-matrix printer is still used by some business establishments because its mechanical pressure enables the producing of carbon and carbon-less copies.

Thermal Printer

This is very common among department stores and malls. Thermal printer are convenient to be used by cashiers because it allows the calculations and giving the print out at the same time in fast manner. Fax machines also have this kind of technology. This, however, works only on papers that are heat sensitive. It operates by having the heated pins pushed against the medium.

Plotters Printer

This type of printer is ideal for printing larger drawings. High quality print out is made out of having the pen plotters pen move across the surface of the medium. This is the most unique printer so far invented and available in the

market.