Computer

Input and Output Devices

Class 3

🎯 Learning Objectives

📖 Let Us Begin!

When Ravi uses a computer, he types on the keyboard and sees words appear on the screen. When Meena records her voice, the computer listens through the microphone and plays it back through the speakers. In all these cases, information is either going INTO the computer or coming OUT of it.

Devices that send information to the computer are called input devices. Devices that bring information out from the computer are called output devices. Some special devices can store information for later use — these are called storage devices.

What is an Input Device?

An input device is any device we use to give data or instructions to the computer. Think of it as talking TO the computer.

Think about it: When you speak to a friend, you are giving them information. Similarly, when you type on a keyboard, you are giving information to the computer!
Common input devices — keyboard, mouse, microphone, scanner, webcam, joystick
Input DeviceWhat it doesDaily Life Example
KeyboardUsed to type letters, numbers, and symbolsRavi types his name in a form at school
MouseUsed to point, click, and select items on screenMeena clicks on a game icon to open it
MicrophoneCaptures sound and voiceSita speaks into the mic during an online class
ScannerCopies a paper document into the computerArjun scans his drawing to send to his teacher
WebcamCaptures video and photosRavi uses the webcam for a video call with his grandparents in Chennai
JoystickUsed to control movement in gamesArjun uses a joystick to play a car racing game
TouchpadA flat pad on laptops used instead of a mouseMeena moves her finger on the touchpad to move the cursor
Light PenA pen-shaped device used to draw or select on screenSita uses a light pen to draw a picture on the computer

What is an Output Device?

An output device is any device that brings information out of the computer so we can see, hear, or use it. Think of it as the computer talking back to us.

Common output devices — monitor, printer, speakers, projector, headphones
Output DeviceWhat it doesDaily Life Example
MonitorDisplays text, images, and videos on screenMeena watches a story on the monitor
PrinterPrints documents and pictures on paperSita prints her project report for school
SpeakersProduce sound — music, voices, alertsArjun listens to a Hindi song through the speakers
ProjectorProjects the screen image on a large wall or boardThe teacher uses a projector to show a map to the whole class
HeadphonesSmall speakers worn on the ears for private listeningRavi wears headphones to listen to an English lesson without disturbing others
PlotterPrints large drawings like maps and building plansAn architect uses a plotter to print a house design

Touchscreen — Both Input and Output!

A touchscreen is a special device that works as both an input device and an output device at the same time.

Examples of Touchscreens

Mobile phones, tablets (like iPads), ATM machines at banks, ticket booking machines at railway stations, and smart boards in classrooms all use touchscreens.

When Meena taps on a game icon on her tablet, she is giving input. When the game appears on the screen, the tablet is giving output. The same screen does both jobs!

Next time you use a mobile phone or tablet, notice how the screen shows you things (output) AND lets you touch and tap to give commands (input). It does two jobs at once!

Storage Devices

A storage device is used to save (store) data so that we can use it later. Without storage devices, all our work would be lost when we turn off the computer.

Storage devices — pen drive, hard disk, CD/DVD
Storage DeviceWhat it doesDaily Life Example
Pen Drive (USB Flash Drive)A small device that stores files and can be carried in your pocketRavi saves his school project on a pen drive and takes it to school
Hard DiskA large storage device inside the computer that stores all files, programs, and the operating systemAll of Meena's photos, games, and homework are saved on the hard disk
CD / DVDA flat, round disc that stores music, videos, or softwareArjun watches a movie on a DVD. Sita installs educational software from a CD.
Memory Card (SD Card)A tiny card used in phones and cameras to store photos and videosSita's camera uses a memory card to save all the photos she takes
Think of a storage device like a school bag for your computer files. Just like you carry your books in a bag, a pen drive carries your files from one computer to another!

The Key Difference

Input vs Output vs Storage — Easy Way to Remember

Input = Giving information TO the computer (you → computer)

Output = Getting information FROM the computer (computer → you)

Storage = Saving information for later use (computer ↔ device)

A keyboard sends your typing to the computer — it is an INPUT device.
A monitor shows you what the computer has processed — it is an OUTPUT device.
A pen drive saves your files to carry them — it is a STORAGE device.
A touchscreen lets you tap AND shows you results — it is BOTH input and output!

Flow diagram: Input devices → Computer → Output devices, with storage devices connected

📝 Key Words

WordMeaning
Input deviceA device used to give data or instructions to the computer
Output deviceA device that brings results or information out of the computer
Storage deviceA device used to save data for later use
KeyboardAn input device with keys for typing letters and numbers
MonitorAn output device that displays information on a screen
MicrophoneAn input device that captures sound and voice
PrinterAn output device that prints documents on paper
ScannerAn input device that copies paper documents into the computer
ProjectorAn output device that displays images on a large screen or wall
TouchscreenA device that works as both input and output
Pen DriveA small portable storage device (also called USB flash drive)
Hard DiskA large storage device inside the computer
CD / DVDA flat round disc used to store music, videos, or software
JoystickAn input device used to control games
HeadphonesAn output device worn on ears for private listening
⭐ Key Points to Remember

Finished learning? Now test what you know!