ICT Class 9 - Input Output-Devices Notes

Input and Output Devices

Welcome to the chapter on Input and Output Devices for Class 9. In this chapter, you will learn about different devices that help us give instructions to the computer (input devices) and devices that show us the results (output devices). By the end of this chapter, you will be able to identify, explain, and differentiate between input and output devices.

Introduction

Computers use various devices to receive data from users and to display or share the results. These devices are called input and output devices.

Input Devices

Input devices are used to enter data and instructions into the computer. They help users communicate with the computer.

• Keyboard: Used to type text, numbers, and commands.
• Mouse: Used to point, click, and select items on the screen.
• Scanner: Used to convert physical documents and images into digital form.
• Microphone: Used to input sound or voice into the computer.
• Webcam: Used to capture live images and videos.
• Touchscreen: Allows users to interact directly with what is displayed by touching the screen.

Output Devices

Output devices show the results of the computer’s work. They help users see, hear, or get the output from the computer.

• Monitor: Displays text, images, and videos on the screen.
• Printer: Produces a paper copy (printout) of documents and images.
• Speaker: Produces sound, music, and voice output.
• Projector: Shows computer output on a large screen for many people to see.
• Headphones: Allow users to listen to audio privately.

Difference Between Input and Output Devices

• Input devices send data to the computer.
• Output devices receive data from the computer and present it to the user.

Examples

• Input: Typing a letter using a keyboard.
• Output: Seeing the letter appear on the monitor.
• Input: Speaking into a microphone.
• Output: Hearing your recorded voice through speakers.

Practice Questions

1. Name three input devices and three output devices.
2. What is the main function of a scanner?
3. How does a printer differ from a monitor?
4. Is a touchscreen an input device, output device, or both? Explain.
5. Give an example of using both an input and output device together.

Challenge Yourself

• Draw and label five input and five output devices.
• Find out about any new input or output device not mentioned here and write a few lines about it.

Did You Know?

• Some devices, like touchscreens and VR headsets, can work as both input and output devices!
• Braille displays are special output devices for visually impaired users.

Glossary

• Input Device: A device used to enter data into a computer.
• Output Device: A device used to display or present data from a computer.
• Scanner: An input device that converts paper documents into digital form.
• Projector: An output device that displays images on a large screen.

Answers to Practice Questions

1. Input: Keyboard, mouse, scanner. Output: Monitor, printer, speaker.
2. To convert physical documents and images into digital form.
3. A printer gives a paper copy, while a monitor shows output on a screen.
4. Both. A touchscreen lets you give input by touching and also shows output on the screen.
5. Typing on a keyboard (input) and seeing the text on a monitor (output).

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Understanding input and output devices helps you use computers better and smarter!