Output and input devices. The main input / output devices of information

Every day, sitting down at his workplace in the office, a person takes a mouse in one hand and begins to perform his duties. He knows why he needs a keyboard, a printer, a scanner, but he does not even realize that they have their official name. All these are input and output devices.

How it works

All devices in the personal computer are controlled by the central processor. To ensure interaction with it, the output and input devices address requests to the south bridge - the logic element of the motherboard. It serves to provide communication and processing of requests from external devices to the north bridge or central processor, if there is no bridge.

In general, computer science deals with the study of the structure of a personal computer. Input and output devices, it defines as components of a typical personal computer, providing the relationship of the user with the computer. But before proceeding to describe all the devices, the basic input-output device deserves a separate mention. It's also BIOS. This chip on the motherboard of the personal computer provides an initial check of all connected devices and starts the operating system.

Classification

The input and output devices of personal computer information can be classified in different ways. The determining factor for this will be their functional responsibilities.

The first item will be the main input-output devices. In fact, you could only specify one item here - the keyboard, since without it no user's computer will continue to download. You can completely turn off the monitor and mouse, but without a keyboard, the computer will not work. The exception is the server computers that work without any external devices connected. So, the basic input / output devices, without which the average user can not work, is:

• keyboard;
• monitor;
• mouse.

You can also allocate additional input-output devices:

• Printers;
• Scanners;
• joystick;
• projector;
• Also, I / O devices are audio devices.

This is not a complete list of possible devices that interact with the user, they can be listed for a very long time. So let's look at the computer's input / output devices in more detail.

Monitors

Computer monitors have undergone many changes in their history. Starting from old, using a cathode-ray tube, and ending with a modern LCD.

By itself, a monitor or display is a device used to output graphic information to the end user. They can be divided into several features.

1. By type of information.

• Alphanumeric. These displays are intended to output only textual information.
• Graphic. With these monitors we come across every day, sitting down at the personal computer. They are designed to present information in a graphic form, including video.

2. By type of screen.

• CRT. A monitor based on a cathode-ray tube, so you might have worked in 2000.
• LCD - liquid crystal "flat" display, used now everywhere. Also this type of monitor is used in laptops.
• Plasma.
• Laser - in mass production has not yet arrived.

Keyboards

What about the keyboards? Fantasy producers in this area stepped far ahead, and a sense of humor pushes on the most daring experiments.

Among the keyboards you can find minimalistic options - without a side additional panel with numbers, and huge game keyboards with built-in joysticks, additional buttons and speakers. There are keyboards with an additional USB-connector and pink keyboards with "incomprehensible buttons" for "blondes". There are also silicone, folding keyboards to make it easier to carry around, or just folding three times.

If you are going to buy yourself a keyboard, just go to the computer store and choose the one that you like.

Mouse

Computer mice are such computer input / output devices, without which the normal user's work is impossible. If the advanced user can navigate through folders and files, as well as some programs and games exclusively using the keyboard, then an ordinary person simply can not do it. For all time, computer mice have undergone not so much changes.

The first mice worked on the basis of a ball in the base. Moving it in different directions, the ball rotated and controlled the controllers.

Then he was replaced by optical mice based on LEDs. The first generation of optical mice required the mandatory presence of a special mat, which was hatched, contributing to increased light reflectance of the surface. Moreover, the first mouse rugs were personal, they could not be replaced by others.

The second generation of optical mice has a more complex device. At the bottom of the mouse a mini video camera is installed, continuously making micrographs of the surface and comparing them with each other to determine the displacement of the device.

A newer device is a semiconductor laser mouse. Among their advantages are low power consumption, reliability, no glow.

Another option mouse is found in the form of a supplement to the graphics tablet. Such induction mice are quite inconvenient to use, because they can not be replaced by more convenient ones, on the arm, and increased accuracy is discredited by a small possibility to move away from it at a distance from the tablet.

Printers

These are the output devices for printing. For all of its existence, printers have not changed much. Technologies are developing, jet printers are replaced by laser printers, but previous generations also continue to live. What is the reason for this? The fact is that different types of printers are suitable for different types of printing. They all perform one function and do not differ much in design. The following types of printers are available:

• Matrix;
• Inkjet;
• Laser;
• Thermal printers.

In the matter of choosing such a device, people usually adhere to personal preferences and habits. However, if you are going to print photos on it, and not just text documents, then laser is more suitable for you due to the higher quality of printing.

Scanners

Device for entering information into the computer. The peculiarity is that the scanners make information in the PC exclusively in a graphic form. The development of scanners has stalled solely on the change in their size. At first they became smaller and smaller, and then they were replaced by huge "combines" - output and input devices that combine a photocopier, a printer and a scanner.

Sound

Each of us likes to watch movies, listen to music at home. Speakers, headphones, audio systems and home theaters, as well as headsets and microphones - all this applies to audio output and input devices.

There are many different microphones and speakers that differ in the quality of audio recording or playback, respectively. Probably, any person can determine for himself how good the sound of a particular speaker is. When choosing an audio system, it is also recommended to follow the design and power to your taste.

Video

To work with video graphics, there are special devices for output and input of information - cameras and projectors.

Projector - a device designed to create an image of an object on a large screen. The following kinds of projectors stand out:

• Diascopic . The image appears due to the passage of light rays through a transparent film with a picture.
• Episcopic . Creates an image using the projection of reflected rays.
• Epidiascopic creates on the screen an image of both transparent and opaque objects.
• Multimedia projector is directly related to the topic of the article. This device is the output of graphic information from the computer to a large surface.

As for the cameras, then there is no need to tell anyone. In most cases, the larger the resolution of the shooting camera, the better the finished picture. With the advent of laptops, USB-cameras began to be replaced with built-in laptop monitor.

Advice

After reading this article, you learned what output and input devices exist, what types they are divided into and what kinds of devices are relevant for today. If you are going to independently equip your working and playing place, and also choose the devices that you want to have at home on hand, then this article should help you with the choice of gadgets.

When you go to a computer store, remember that sellers can offer you something more expensive or already stale, outdated goods. Do not be lazy before going to the Internet and read customer reviews about various models of external devices.

Remember the main rule of the buyer: more expensive does not mean better. In a computer store, buying a printer or a headset, you can easily overpay for the brand, and then long regret about their purchase.

An example is HP printers. Yes, they are considered to be one of the best, however, replacing the completed cartridge or just a small malfunction will fly into you pretty much because of the manufacturer's fame.

When buying a sound system, do not hesitate to check the sound and performance of the speakers. And if you are going to buy a webcam, then test its image, because not always the permission stated in the documentation can match the available one.

And the main rule. When purchasing a product, ask the seller for warranty information. For example, for some devices, services require a box in which the unit was supplied. A vivid example - laptops "Asus". In most cases, anywhere on the store's website there is no information that manufacturers require a branded box when contacting a service center.

Be careful and have a good shopping for you!