Input Output Devices

Input Device-An input devices is a hardware device that is used to send data or instructions to a computer or other electronic device. Input devices allow users to interact with the computer by providing a way to enter data, commands, and other instructions into the system.

peripheral device, also known as peripheral, computer peripheral, input-output device, or input/output device, any of various devices (including sensors) used to enter information and instructions into a computer for storage or processing and to deliver the processed data to a human operator or, in some cases, a machine controlled by the computer. Such devices make up the peripheral equipment of modern digital computer systems.

Peripherals are commonly divided into three kinds: input devices, output devices, and storage devices (which partake of the characteristics of the first two).(input output devices ) An input device converts incoming data and instructions into a pattern of electrical signals in binary code that are comprehensible to a digital computer. An output device reverses the process, translating the digitized signals into a form intelligible to the user. At one time punched-card and paper-tape readers were extensively used for inputting, but these have now been supplanted by more efficient devices.

Input devices-Input devices include typewriter-like keyboards; handheld devices such as the mouse, trackball, joystick, trackpad, and special pen with pressure-sensitive pad; microphones, webcams, and digital cameras. They also include sensors that provide information about their environment—temperature,(input output devices )  pressure, and so forth—to a computer. Another direct-entry mechanism is the optical laser scanner (e.g., scanners used with point-of-sale terminals in retail stores) that can read bar-coded data or optical character fonts.

Output devices-Output equipment includes video display terminals, ink-jet and laser printers, loudspeakers,(input output devices )  headphones, and devices such as flow valves that control machinery, often in response to computer processing of sensor input data. Some devices, such as video display terminals and USB hubs, may provide both input and output. Other examples are devices that enable the transmission and reception of data between computers—e.g., modems and network interfaces.

Storage Devices.-(input output devices ) most auxiliary storage devices —

as, for example, CD-ROM and DVD drives, flash memory drives, and external disk drives also double as input/output devices (see computer memory). Even devices such as smartphones, tablet computers, and wearable devices like fitness trackers and smartwatches can be considered as peripherals, albeit ones that can function independently.

There are many different types of input devices (input output devices ) , each designed for a specific purpose. Some of the most common input devices include:

1.   Keyboard: A keyboard is a device that allows users to enter alphanumeric data and commands into a computer by pressing keys.

2.   Mouse: A mouse is a pointing device that allows users to move a cursor on the screen and interact with graphical user interfaces (GUIs) by clicking buttons.

3.   Scanner: A scanner is a device that is used to convert physical documents and images into digital format.

4.   Microphone: A microphone is a device that allows users to input audio into the computer, either for recording or for voice recognition purposes.(input output devices ) 

5.   Webcam: A webcam is a camera that is used to capture video and images and input them into the computer.

Output Device-An output device is a hardware device that is used to display or output data or information from a computer or other electronic device. Output devices allow users to see, hear, or otherwise perceive the results of their interactions with a computer system.

Some of the most common output devices include:

1.   Monitor: A monitor is a display device that displays visual output from a computer, such as text, images, and video.(input output devices ) 

2.   Printer: A printer is a device that produces hard copies of electronic documents or images.

3.   Speaker: A speaker is a device that produces audio output, such as music or speech.

4.   Headphones: Headphones are an output device that is worn on the ears to produce audio output.

5.   Projector: A projector is a device that projects visual output onto a larger screen or surface, such as a wall or projector screen.(input output devices ) 

Interface-In computing, an interface refers to the connection point between different hardware or software components, or between a human and a computer system. Interfaces allow users to interact with computer systems and other devices, and they also enable different components to communicate with each other.

There are several types of interfaces, including:

User interface- A user interface (UI) is the point of interaction between a human user and a computer system. This can include graphical user interfaces (GUIs), command-line interfaces (CLIs), and other types of interfaces that allow users to input commands and data into a computer system.

Application programming interface: An application programming interface (API) is a set of rules and protocols that define how different software components can interact with each other. APIs allow developers to create software applications that can interact with other applications or systems, such as web services or databases.

Hardware interface: A hardware interface refers to the physical connections and protocols used to connect different hardware components, such as the USB interface used to connect a keyboard or mouse to a computer.

Network interface: A network interface is the connection point between a computer system and a network. This can include Ethernet, Wi-Fi, or other types of network interfaces that allow computers to communicate with each other over a network.(input output devices ) 

Operating system interface: An operating system interface is the set of protocols and APIs that allow software applications to interact with the operating system. This can include system calls, device drivers, and other components that enable applications to use system resources.(input output devices ) 

Various standards for connecting peripherals to computers exist. For example, serial advanced technology attachment (SATA) is the most common interface, or bus, for magnetic disk drives. A bus (also known as a port) can be either serial or parallel, depending on whether the data path carries one bit at a time (serial) or many at once (parallel). Serial connections, which use relatively few wires, are generally simpler than parallel connections. (input output devices ) Universal serial bus (USB) is a common serial bus. 

Following are some of the important input devices which are used in a computer −

1. ·         Keyboard

2. ·         Mouse

3. ·         Joy Stick

4. ·         Light pen

5. ·         Track Ball

6. ·         Scanner

7. ·         Graphic Tablet

8. ·         Microphone (Mic)

9. ·         Magnetic Ink Card Reader(MICR)

10. ·         Optical Character Reader(OCR)

11. ·         Bar Code Reader (BCR)

12. ·         Optical Mark Reader(OMR)

INPUTDEVICES,OUTPUTDEVICES, INTERFACEDEVICES, OUTPUT DEVICES, TYPESOFINTERFACE

INPUT DEVICES (input output devices ) 

Keyboard

Keyboard is the most common and very popular input device which helps to input data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing additional functions.

Keyboards are of two sizes 84 keys or 101/102 keys, but now keyboards with 104 keys or 108 keys are also available for Windows and Internet.

The keys on the keyboard are as follows −

Keys & Description

Typing Keys

These keys include the letter keys (A-Z) and digit keys (09) which generally give the same layout as that of typewriters,

Numeric Keypad

It is used to enter the numeric data or cursor movement. Generally, it consists of a set of 17 keys that are laid out in the same configuration used by most adding machines and calculators.

Function Keys

The twelve function keys are present on the keyboard which are arranged in a row at the top of the keyboard. Each function key has a unique meaning and is used for some specific purpose.

Control keys

These keys provide cursor and screen control. It includes four directional arrow keys. Control keys also include Home, End, Insert, Delete, Page Up, Page Down, Control(Ctrl), Alternate(Alt), Escape(Esc).

Special Purpose Keys

Keyboard also contains some special purpose keys such as Enter, Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Screen.

Mouse

Mouse is the most popular pointing device. It is a very famous cursor-control device having a small palm size box with a round ball at its base, which senses the movement of the mouse and sends corresponding signals to the CPU when the mouse buttons are pressed.

Generally, it has two buttons called the left and the right button and a wheel is present between the buttons. A mouse can be used to control the position of the cursor on the screen, but it cannot be used to enter text into the computer.

Advantages

• ·         Easy to use

• ·      ,   Not very expensive

• ·         Moves the cursor faster than the arrow keys of the keyboard.

Light Pen

Light pen is a pointing device similar to a pen. It is used to select a displayed menu item or draw pictures on the monitor screen. It consists of a photocell and an optical system placed in a small tube.

When the tip of a light pen is moved over the monitor screen and the pen button is pressed, its photocell sensing element detects the screen location and sends the corresponding signal to the CPU.

Track Ball

Track ball is an input device that is mostly used in notebook or laptop computer, instead of a mouse. This is a ball which is half inserted and by moving fingers on the ball, the pointer can be moved.

Since the .whole device is not moved, a track ball requires less space than a mouse. A track ball comes in various shapes like a ball, a button, or a square.

Digitizer

Digitizer is an input device which converts analog information into digital form. Digitizer can convert a signal from the television or camera into a series of numbers that could be stored in a computer. They can be used by the computer to create a picture of whatever the camera had been pointed at.

Digitizer i.s also known as Tablet or Graphics Tablet as it converts graphics and pictorial data into binary inputs. A graphic tablet as digitizer is used for fine works of drawing and image manipulation applications.

Joystick.

Joystick is also a pointing device, which is used to move the cursor position on a monitor screen. It is a stick having a spherical ball at its both lower and upper ends. The lower spherical ball moves in a socket. The joystick can be moved in all four directions.

The function of the joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing (CAD) and playing computer games.

Microphone

Microphone is an input device to input sound that is then stored in a digital form.

The microphone is used for various applications such as adding sound to a multimedia presentation or for mixing music.

Scanner

Scanner is an input device, which works more like a photocopy machine. It is used when some information is available on paper and it is to be transferred to the hard disk of the computer for further manipulation.

Scanner captures images from the source which are then converted into a digital form that can be stored on the disk. These images can be edited before they are printed.

Magnetic Ink Card Reader (MICR)

MICR input device is generally used in banks as there are large number of cheques to be processed every day. The bank's code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable.

This reading process is called Magnetic Ink Character Recognition (MICR). The main advantages of MICR is that it is fast and less error prone.

Bar Code Readers (BCR)

Bar Code Reader is a device used for reading bar coded data (data in the form of light and dark lines). Bar coded data is generally used in labelling goods, numbering the books, etc. It may be a handheld scanner or may be embedded in a stationary scanner.

Bar Code Reader scans a bar code image, converts it into an alphanumeric value, which is then fed to the computer that the bar code reader is connected to.

Optical Character Reader (OCR)

OCR is an input device used to read a printed text.

OCR scans the text optically, character by character, converts them into a machine readable code, and stores the text on the system memory.

Optical Mark Reader (OMR)

OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It is used where one out of a few alternatives is to be selected and marked.

It is specially used for checking the answer sheets of examinations having multiple choice questions.