Once you finish this article you will have a better idea about these output devices.

So, let's start. First of all, what it is an output device?

When you discuss computer output devices it's important to have a clear definition of what output is.

Output is the goal of input and processing. It provides the information users need to work and make decisions.

Output used by a computer output device (or any machine) often is an intermediate result. Eventually it will be processed into a form that can be used by people. Or in other words, a computer output device is any peripheral device that presents output from the computer.

The first computer output device is placed just in front of you. The monitor. Therer are several basic types of monitors. Here are the groups - CRT monitors, Flat technology monitors, LCD displays, and Gas plasma monitors.

Let's start with the first type of computer output device mentioned before, in terms of the monitor: The CRT monitors. The first thing that you see in the name of this type is the abbreviation. What does it mean?

It stands for Cathode ray tube. This is the traditional monitor type, as opposed to the newer LCD and plasma screens. Inside a CRT is a vacuum tube with three electron guns at one end and a flat surface, which is the inside of the screen at the other. The electron guns shoot beams of negatively charged electrons at the phosphors lining the front of the tube. Exciting the phosphors creates thousands of pixels (picture elements), which consist of a triad of red, green, and blue.

When the beams hit the phosphors, they glow and create the image you see on-screen. (There are several different types of CRTs, of course, but all utilize some special mechanism to separate the phosphors.)

This is a very short and simplified explanation about the CRT monitors, but nonetheless it may be helpful in discussing computer output devices.

Let's move on to the next type of computer output devices, in terms of monitors. This is the Flat technology monitors. These are often abbreviated as FTM. Flat technology monitors are monitors that have a flat display screen to reduce glare. Conventional display screens are curved, which makes them more susceptible to reflections from external light sources.

They are pretty popular nowadays, but not as much as the well known LCD monitors.

LCD stands for "Liquid-Crystal Display." LCDs are super-thin displays that are used in laptop computer screens and flat panel monitors. Smaller LCDs are used in handheld TVs, PDAs, and portable video game devices. The image on an LCD screen is created by sandwiching an electrically reactive substance between two electrodes.

LCD panels differ from CRT in the way image is presented to us on the screen. LCD panels have a fixed number of liquid crystal cells and display only one resolution at full-screen size. There are no convergence problems with LCD panels, because each cell is switched on and off individually, as opposed to CRT screens, which rely on convergence from electron guns for clarity.

LCD panels do not suffer from flicker or resolution problems like their counterparts.

Since LCD screens are based on the principle of blocking light (rather than emitting it), they use up much less power than standard CRT (Cathode-Ray Tube) monitors.

Now let's say a few words about the last type of monitors. This is the gas panel monitors. These monitors are flat panel monitors that use gas plasma technology, providing a layer of gas deposited between two sheets of material. When voltage is applied, the gas glows a produces the pixels that form the image.

You can think of a gas-plasma display as a collection of very small neon bulbs. Images on gas-plasma displays generally appear as orange objects on top of a black background. Gas plasma monitors offer larger screen sizes and higher display quality than LCD monitors, but are much more expensive. They also can be hung directly on the wall.

So, that was everything about computer output devices known as monitors you needed to know. Hopefully you have found information which may be useful for you.

Now, let's say a few words about the next type of computer output devices, or the printer.

Just like the monitors, the computer output device known as printers are divided into different groups. But before that you may want to learn something more about printers. The printer is nothing more than a device that prints text or illustrations on paper. There are many different types of printers. In terms of the technology utilized, printers fall into the following categories: Dot-matrix printers, Line printers, Nonimpact printers, Ink-jet printers, Laser printers, Thermal printers.

Ok, let's start with the simplest printer (computer output device) of all. This is the dot–matrix printer, as you may suggest. What can be said about it? Well, not that much, because it is not so widely used, since the advent of the more sophisticated printers.

Here's how it works...

The printer creates characters by striking pins against an ink ribbon. Each pin makes a dot and combinations of dots form characters and illustrations. The characters produced by dot matrix printers are similar to those fashioned on certain electronic scoreboards.

Dot-matrix printers sometimes are known as character printers. An older type of character printer, the daisy wheel printer, prints a solid character. Although noted for high-quality printing, daisy wheel printers are slower and less flexible than dot-matrix printers.

Now, here comes something more for the Line printers. This type of printers contain a chain of characters or pins that print an entire line at one time. Line printers are known to be very fast, but unfortunately produce low-quality print. The most common types of line printers in use today are band printers, chain printers, and drum printers. Each uses a slightly different technology to produce characters, but all are very fast because each character on the line has its own print hammer which allows for 132 printing positions.

The output of these high-speed printers is too fast to be measured in characters per second (as other printers are). Instead, they are measured in lines per minute. Some of these printers can produce over 3000 lines of type per minute (almost 80,000 words per minute).

So, it is time to say a few words about printer computer output devices known as Nonimpact printers. These printers are one of the most preferred printers. These printers use a number of different technologies to produce an image on paper without striking through an inked ribbon. In the past few years, laser printers have become the most popular nonimpact type of printer.

Another type of printer computer output device is the ink–jet printers. That is why they represent the fastest growing segment of the printer market. One attraction of noimpact printers is their quiet operation. Imagine the noise level in an office with several impact printers operating simultaneously!

Next come the well-known printer computer output device...Ink –jet printers. As you probably know these printers are the most popular printers for home use. The mechanism of printing is the following. The ink, which can be green, red, or blue, is sprayed on the paper. Then the sheet of paper should not be touched for a while, because the ink needs some time to dry. And one of the reasons why these printers are so popular is because they produce high-quality text and graphics.

Now, let's talk about the best printer computer output devices... Laser printers. These output devices use the same technology as copy machines. Although laser printers are popular, they do not handle all printing jobs well. Special feeders are needed to print multiple envelopes, and multipart forms cannot be used at all.

And now, let's finish the review on printers with the Thermal printer. This type of printers in fact represents an inexpensive printer that works by pushing heated pins against heat-sensitive paper. These printers are widely used in calculators and fax machines. Although dye-sublimation printers (another name for this type of printers) produce photographic-quality images suitable for desktop publishing and professional presentations. The added data can cause the printer to run slowly.

So, these computer output devices are the most needed and mostly used devices among all, but they are not at all the only ones. Another output device is the CD – ROM, the stereo speakers, the magnetic discs and tapes, the blue tooth, the plotter, and many many others.