Skip to main content

What is Input and Output devices

What is the difference between an input and output device?



An input device sends information to a computer system for processing, and an output device reproduces or displays the results of that processing. Depending on the interaction, a device can be both, referred to as an input/output or I/O device.


Examples

An input device can send data to another device, but it cannot receive data from another device. Examples of an input device include a computer keyboard and mouse, which can send data (input) to the computer, but they cannot receive or reproduce information (output) from the computer.




An output device can receive data from another device, but it cannot send data to another device. Examples of an output device include a computer monitor, projector, and speakers, which can receive data (output) from the computer, but they cannot send information (input) to the computer. An input/output device can send data to another device and also receive data from another device. Examples of an input/output include a computer CD-RW drive and USB flash drive, which can send data (input) to a computer and also receive data (output) from a computer.




Keyboard


The keyboard is one of the common input device of computer.It is a typewriter like device which is used to type in the letters, digits and commands. The layout of the keyboard is like that of the QWERTY typewriter, although there are some extra command and function keys provided therein. Basically a keyboard contains a matrix of switches (one switch per key):Each key, when pressed,sends a digital code to the computer that determines which key has been pressed e.g.,if you press 'A' when caps lock button is On, a code of 01000001 is sent to computer; computer then translates this code to determine that you pressed 'A' from the keyboard. Substantial development has taken place in the ergonomics of keyboard design to ensure that operator strain is minimal.





Keyboard interfaces

Today, most desktop computer keyboards connect to the computer using either USB or Bluetooth for wireless communication. Before USB, a computer may have used PS/2 or AT (Din5) as a keyboard interface.





     Advantages

  • Relible way of inputing text and Number.
  • Available in variery of formats.

     Disadvantages

  • Not useful for entering some spcific type of data (e.g. pictures,diagrams, voice, video etc.)
  • Very slow while accessing menu options or selecting various objects on screen.
  • Very slow while moving windows or other objects.
  • Not much useful for enlarging or changing sizes of windows on screen.



Pointing device

A pointing device is an input interface (specifically a human interface device) that allows a user to input spatial (i.e., continuous and multi-dimensional) data to a computer. ... Movements of the pointing device are echoed on the screen by movements of the pointer (or cursor) and other visual changes.





An input device used to move the pointer (cursor) on screen. The major pointing device is the mouse for the desktop computer and the touchpad for the laptop, although many road warriors bring along a mouse. Pointing sticks are available on some laptops, and a small number of users prefer trackballs over the mouse. See mouse, touchpad, trackball and pointing stick.


     Mouse

A computer mouse is an input device that is most often used with a personal computer. Moving a mouse along a flat surface can move the on-screen cursor to different items on the screen. Items can be moved or selected by pressing the mouse buttons (called clicking).[1] It is called a computer mouse because of the wire that connects the mouse to the computer. The people who designed the first computer mice thought that it looked like the tail on a mouse. Today, many computer mice use wireless technology and have no wire.

     Advantages

  • Ideal for pointing objects/options on desktop computers.
  • Most familliar and easily to use pointing device.

     Disdvantages

  • Need a flat surface close to computer.
  • A mouse can not easily be used with a laptop or a notebook or a palm top computrs.

Comments

Post a Comment

Thank you for comment.

Popular posts from this blog

Classification of computer based on their cost size and confriguration.

TYPES OF COMPUTER Computer and it's Type Computers are classified by the type of data they are desinged to process. Data may be obtained either as a result of countig of through the use of same measuring instrument. Data that are obtained by counting are called discreate data are total numbers of students in a classroom. Data that must be obtained throgh measurement are called continous data. For example, continious data are the speeds an automobile measure by speedmotor or the tempreature of a patient as masured by a thermometer. Classification of computer based on their cost size and confriguration. In this category computers are classified as micro-computer. mainfraim compute...
Post a Comment
Read more

Use of statement in python

Use of statement of Python: Use of if – else statement:-if – else is the variation of if statement. We attach condition with if statement if given condition is true then if block code will executed and if the given condition is false then else block code will executed. The syntax of if – else statement is given below:- if condition: Statement 1 Statement 2 else: Statement 3 Statement 4 Write a program in python to check the given number is even or odd. n=input(“Enter a number : ”) if n%2==0: print “The number ”,n,”is even” else: print “The number”,n,”is odd” Use of if-else ladder:- In Python language the switch statement is not worked. In Python we use if-else ladder in spite of using switch. The syntax of if-else ladder is given below:- if condition1: Statement 1 elif condition 2: Statement 2 elif condition 3: Statement 3 >br> else: Statement 4 Write a program in python to find greatest number in three numbers. a=input(“Enter firs...
Post a Comment
Read more

computer and it's generation

Computer and It's GENERATION Let us first define the term computer. Computer is defined in the Oxford dictionary as "An automatic electronic apparatus for making calculations or controlling operations that are expressible in numerical or logical terms." The definition clearly categorise computer as electronic apparatus although the first computers were mechanical and electromechanical apparatus. The definition is also pointing towords the two major areas of computer application viz. data processing and computer assisted controls/operations. The another important confluence of the definition is the fact that the computer can perform only those operations/calculations which can be expressed in logical or numerical terms. Computer Generation From the early 1940's to the present, Computer scientists have been able to identify clear-cut stages in the development of computer technology. With each stage, radical change in electronics have taken place. As a resu...
2 comments
Read more