Lecture Notes on Input and Output Devices (Cambridge IDCSE ICT Chapter 2)

Introduction

• Presenter: Kumi Tassen
• Focus: Characteristics, uses, advantages, and disadvantages of input and output devices.

Input Devices

Definition

• Input Device: A hardware device used to enter data into a computer.
• Categories: Manual Input Devices and Direct Data Entry Devices.

Manual Input Devices

1. Keyboard

   • Types: Wired, Wireless, Virtual (touchscreen)
   • Advantages: Easy to use, fast text entry, easy verification.
   • Disadvantages: Slower than direct data entry, takes up space.

2. Numeric Keypads

   • Usage: ATMs, data entry in spreadsheets.
   • Advantages: Faster than keyboards for numeric data, portable.
   • Disadvantages: Small keys, difficult text entry on old phones.

3. Mouse

   • Types: Wired, Wireless
   • Uses: Opening, closing, minimizing software.
   • Advantages: Fast selection, takes up less space.
   • Disadvantages: Requires flat surface, easily damaged.

4. Touchpad

   • Used in laptops.
   • Advantages: No need for separate mouse, fast.
   • Disadvantages: Difficult for those with hand issues, less intuitive.

5. Tracker Ball

   • Ergonomic alternative to mouse.
   • Advantages: Easier, more robust and accurate.
   • Disadvantages: Costly, may require training.

6. Remote Control

   • Uses: TVs, DVDs, robots.
   • Advantages: Easy to use, works from distance.
   • Disadvantages: Signal can be blocked, complex for advanced functions.

7. Joystick

   • Mainly for gaming and simulations.
   • Advantage: Easier navigation.
   • Disadvantage: Harder to use than standard mouse.

8. Touchscreens

   • Used in ATMs, POS, phones, tablets.
   • Advantages: Fast entry, user-friendly.
   • Disadvantages: Limited options, can get dirty.

9. Light Pens

   • Used on CRT monitors.
   • Advantages: Accurate, handy.
   • Disadvantages: Lag, outdated.

10. Scanners

    • Convert hard copy to digital.
    • Advantages: Various formats, fast.
    • Disadvantages: Limited quality, slow at high resolutions.

11. Digital Cameras

    • Advantages: Better quality, easy upload.
    • Disadvantages: Requires training, replaces some human jobs.

12. Microphones

    • Use: Speech input, sound recording.
    • Advantages: Fast text entry, aids security.
    • Disadvantages: Large file size, less accurate recognition.

13. Sensors

    • Measure physical quantities.
    • Analog data must be converted to digital for computer processing.
    • Examples: Temperature, pressure, light, sound, humidity, pH.
    • Advantages: Accurate, reliable, low human intervention.
    • Disadvantages: Prone to faults, cost of ADC conversion.

Direct Data Entry Devices

1. Magnetic Stripe Reader

   • Used for cards with magnetic stripes
   • Advantages: Fast, error-free, secure.
   • Disadvantages: Damage-prone, requires contact.

2. Contactless Debit Card Reader

   • Uses radio waves.
   • Advantages: Fast, encrypted, error-free.
   • Disadvantages: Expensive, limited transactions, hack risk.

3. Chip and Pin Reader

   • Advantages: Secure, robust.
   • Disadvantages: Pins can be stolen or forgotten.

4. RFID Readers

   • Used for tracking.
   • Advantages: Long-distance reading, reliable, bidirectional.
   • Disadvantages: Expensive, interference, hackable.

5. Optical Mark Recognition (OMR)

   • Reads marks, used in exams.
   • Advantages: Fast, accurate.
   • Disadvantages: Requires precise form design.

6. Optical Character Recognition (OCR)

   • Converts text to electronic form.
   • Advantages: Fast, less error.
   • Disadvantages: Difficulty with handwriting, accuracy issues.

7. Barcode Readers/Scanners

   • Advantages: Fast, reliable.
   • Disadvantages: Expensive, prone to damage.

8. Quick Response (QR) Code Readers

   • Advantages: Fast, holds more information.
   • Disadvantages: Multiple formats, can transmit malicious code.

Conclusion

• Manual input devices require human effort, direct data entry devices do not.
• Next: Upcoming video on output devices.