1. Input and Output devices
Lecture 5
Zikria Mian

2. • Define Input
• Describe keyboard, pointers and scanners
• Describe image capturing, digitizing and
audio input devices
• Define output
• Describe monitors, printers and audio
outputs
• Discuss combination input and output
devices

3. • Input and output devices are an interface
for the users to interact with the computer.
• Computer understands binary language
only.
• Input devices translate numbers, letters,
actions etc that people understand into a
form that computers can process whereas
output devices translate machine
language into a form that people can
understand.

4. Input Devices
• Scanning devices
– Optical scanners
– Barcode readers
– Character and mark recognition devices
• Magnetic-ink character recognition
• Optical character/mark recognition
– Other scanners?

5. Input devices (continued)
• Image capturing devices
– Digital cameras
– Motion sensors
• Digitizing devices
– Graphics tablets
– Digital notepads
• Audio Input devices
– Voice recognition systems
• Discrete speech recognition
• Continuous speech recognition
– microphones

6. Output devices
• Monitors
– CRTs
– Flat-panel
– Projectors
– E-book readers
– HD TVs
– Features
• Resolution, dot pitch, refresh rate, screen size

7. Output devices (continued)
• Printers
– Dot-matrix
– Inkjet printers
– Photo printers
– Laser printer
– Features
• Resolution, Colour capability, Speed,Memory
• Audio output

8. Combined input/output devices
• Fax machines / MFDs
• Internet telephones
• Touchscreens
• Smart boards
• Joysticks?
• ………

9. Summary
• Definition of input and output device
• Input devices
– Scanners, Image capturing devices, Digitizing
devices, Audio inputs
• Output devices
– Monitors, printers, audio outputs, other
mechanical or robotic reactions*
• Combined input/output devices

10. Summary
• Definition of input and output device
• Input devices
– Scanners, Image capturing devices, Digitizing
devices, Audio inputs
• Output devices
– Monitors, printers, audio outputs, other
mechanical or robotic reactions*
• Combined input/output devices