Cambridge IGCSE Computer Science (0478) · lesson 20 of 35 · 20 min
Input Devices
An input device converts real-world data (text, images, sound, movement) into digital signals the computer can process.
Choosing the Right Input Device
The best input device depends on the data type, environment, and user needs:
- Large amounts of text → keyboard.
- Precise graphical work → graphics tablet.
- Hands-free or accessibility needs → voice/microphone.
- Automated data capture → barcode reader, sensor.
- Mobile/touch environment → touchscreen.
Which input device is most suitable for a supermarket checkout?
- Graphics tablet
- Barcode reader
- Microphone
- Scanner
Answer: Barcode reader
Barcode readers quickly capture product codes at point of sale.
A touchscreen is both an input and output device. Why?
- It displays images and captures touch
- It prints and scans
- It records sound and plays it back
- It stores and retrieves data
Answer: It displays images and captures touch
A touchscreen displays output (images) and captures input (touch gestures) simultaneously.
Which device converts sound waves into digital data?
- Speaker
- Microphone
- Camera
- Sensor
Answer: Microphone
A microphone captures sound waves and converts them to digital audio signals.
Previous lesson: Secondary storage: HDD, SSD, optical, flash
Back to Cambridge IGCSE Computer Science (0478)
Next lesson: Output devices and their applications