i want some brief notes about input and output devices?

Answer 1

hi bala
there are two types of devices input devices and output devices.

INPUT DEVICES
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1. Keyboard

is a peripheral modeled after the typewriter keyboard. Keyboards are designed for the input of text and characters and also to control the operation of a computer.
A 104-key PC US English QWERTY keyboard layout
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A 104-key PC US English QWERTY keyboard layout

Physically, computer keyboards are an arrangement of rectangular or near-rectangular buttons, or "keys". Keyboards typically have characters engraved or printed on the keys; in most cases, each press of a key corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence; other keys do not produce any symbol, but instead affect the operation of the computer or the keyboard itself.

Roughly 50% of all keyboard keys produce letters, numbers or signs (characters). Other keys can produce actions when pressed, and other actions are available by the simultaneous pressing of more than one action key.

2. Mouse

I A device that controls the movement of the cursor or pointer on a display screen. A mouse is a small object you can roll along a hard, flat surface. Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse's tail, and the fact that one must make it scurry along a surface. As you move the mouse, the pointer on the display screen moves in the same direction. Mice contain at least one button and sometimes as many as three, which have different functions depending on what program is running. Some newer mice also include a scroll wheel for scrolling through long documents.

Invented by Douglas Engelbart of Stanford Research Center in 1963, and pioneered by Xerox in the 1970s, the mouse is one of the great breakthroughs in computer ergonomics because it frees the user to a large extent from using the keyboard. In particular, the mouse is important for graphical user interfaces because you can simply point to options and objects and click a mouse button. Such applications are often called point-and-click programs. The mouse is also useful for graphics programs that allow you to draw pictures by using the mouse like a pen, pencil, or paintbrush.


3. Track ball

A trackball is a pointing device consisting of a ball housed in a socket containing sensors to detect rotation of the ball about two axes—like an upside-down mouse with an exposed protruding ball. The user rolls the ball with their thumb, fingers, or the palm of their hand to move a cursor. Tracker balls are common on CAD workstations for ease of use and, before the advent of the touchpad, on portable computers, where there may be no desk space on which to use a mouse. Some clip onto the side of the keyboard and have integral buttons which have the same function as mouse buttons. Trackballs are sometimes seen on computerised special-purpose workstations, such as the radar consoles in an air-traffic control room or sonar equipment on a ship or submarine. Modern installations of such equipment may use mice instead, since most people now already know how to use one. However, military mobile anti-aircraft radars and submarine sonars tend to continue using trackballs, since they can be made much more durable and are more fit for fast emergency use.

Trackballs have had some limited use in computer and video games, particularly early arcade games . One of the more famous games to use one is Centipede. "Football", by Atari, was the first arcade game to use a trackball, released in 1978 for the arcade. Console trackballs, once common in the early years, are now fairly uncommon. The Bandai Atmark, a Japanese console, had a trackball as standard for its gamepad, and the Atari 2600 had one as a peripheral, with a joystick as standard. As of today, trackballs are often in use in pub golf machines (such as Golden Tee) to simulate swinging the club.

4. Joy stick

Joysticks pull off a really neat trick. They take something entirely physical -- the movement of your hand -- and translate it into something entirely mathematical -- a string of ones and zeros (the language of computers). With a good joystick, the translation is so flawless that you completely forget about it. When you're really engaged in a game, you feel like you're interacting with the virtual world directly.

5. Data Glove

A glove equipped with sensors that sense the movements of the hand and interfaces those movements with a computer. Data gloves are commonly used in virtual reality environments where the user sees an image of the data glove and can manipulate the movements of the virtual environment using the glove.

6. Digitizer

A common device for drawing, painting etc...

7. Scanner

In computing, a scanner is a device that analyzes an image (such as a photograph, printed text, or handwriting) or an object (such as an ornament) and converts it to a digital image. Most scanners today are variations of the desktop (or flatbed) scanner The flatbed scanner is the most common in offices. Hand-held scanners, where the device is moved by hand, were briefly popular but are now not used due to the difficulty of obtaining a high-quality image. Both these types of scanners use charge-coupled device (CCD) or Contact Image Sensor (CIS) as the image sensor, whereas older drum scanners use a photomultiplier tube as the image sensor.

8. Touch panel

is a display device that accepts user input by means of a touch sensitive screen. Because of their compact nature and ease-of-use, touch panels are typically deployed for user interfaces in automation systems, such as high-end residential and industrial control. Touch panels are also becoming common on portable computers such as Tablet PCs and consumer devices such as VOIP phones.

The most common types of touch panels are resistive, capacitive and surface wave.

9. Light Pen

A light pen is a computer input device in the form of a light-sensitive wand used in conjunction with the computer's CRT monitor. It allows the user to point to displayed objects, or draw on the screen, in a similar way to a touch screen but with greater positional accuracy. A light pen can work with any CRT-based monitor, but not with LCD screens, projectors or other display devices.

A light pen is fairly simple to implement. The light pen works by sensing the sudden small change in brightness of a point on the screen when the electron gun refreshes that spot. By noting exactly where the scanning has reached at that moment, the X,Y position of the pen can be resolved. This is usually achieved by the light pen causing an interrupt, at which point the scan position can be read from a special register, or computed from a counter or timer. The pen position is updated on every refresh of the screen.

OUT PUT DEVICES
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1. Printer

A computer printer, or more commonly just a printer, is a device that produces a hard copy (permanent human-readable text and/or graphics) of documents stored in electronic form, usually on physical print media such as paper or transparencies. Many printers are primarily used as computer peripherals, and are permanently attached to a computer which serves as a document source. Other printers, commonly known as network printer, have built-in network interfaces (typically wireless or Ethernet), and can serve as a hardcopy device for any user on the network. In addition, many modern printers can directly interface to electronic media such as memory sticks or memory cards, or to image capture devices such as digital cameras, scanners; some printers are combined with a scanners and/or fax machines in a single unit. A printer which is combined with a scanner can essentially function as a photocopier.

2. Computer Monitor

A computer display (also known as a computer monitor, computer screen, or computer video display) is a device that can display signals generated by a computer as images on a screen. (From the Latin verb monere: to warn, advise.) There are many types of monitors, but they generally conform to display standards. Once an essential component of computer terminals, computer displays have long since become standardised peripherals in their own right.

Answer 2

Input And Output Devices Notes

Answer 3

Women have Input Devices and Men have Output Devices :-)

Sometimes they wear Briefs

Hows that?

Answer 4

While normally just an output device: there are printers that are capable of input functions. Some have slots for an SD card so that you can copy pictures to your computer or straight to print. Fax/printers would also have input and output functions (enter data and fax number to send).

Answer 5

input devices are the onse used to input data from an outside environment into the internal computer environment. they include the keyboard..
output devices are the ones that give us results of the inputs we inter. for example we consider printers as output devices because they give us results of the inputs we inter by printing them.