Know and understand characteristics, uses, advantages and disadvantages of input devices including keyboard, numeric keypad, pointing devices, remote control, joystick/driving wheel, touch screen (as an input device), scanners, camera, microphone, se

2 Input and Output Devices – Input Devices

This section covers the main input devices studied for Cambridge IGCSE ICT 0417. For each device the characteristics, typical uses, advantages and disadvantages are outlined.

Keyboard

A keyboard is a set of keys that allows the user to enter alphanumeric data and commands.

• Characteristics: QWERTY layout, function keys (F1‑F12), modifier keys (Shift, Ctrl, Alt), optional numeric keypad.
• Uses: Word processing, programming, data entry, gaming.
• Advantages:

  • Fast and accurate for text entry.
  • Standardised layout – widely supported.
  • Low cost and durable.

• Disadvantages:

  • Requires hand‑eye coordination.
  • Not suitable for users with certain physical disabilities.
  • Limited for drawing or gesture‑based input.

Numeric Keypad

A separate block of keys (0‑9, decimal point, arithmetic operators) used mainly for numeric data entry.

• Characteristics: Usually on the right side of a full‑size keyboard; includes a “Num Lock” key.
• Uses: Accounting, spreadsheets, data entry where large numbers are entered.
• Advantages:

  • Speeds up numeric entry.
  • Ergonomic for repetitive number input.

• Disadvantages:

  • Extra keys increase keyboard size.
  • Not useful for text‑only tasks.

Pointing Devices

Devices that translate hand movement into cursor movement on the screen.

• Types: Mouse, touchpad, trackball, graphics tablet.
• Characteristics: Provide two‑dimensional control; may include buttons or scroll wheels.
• Uses: Selecting icons, drawing, gaming, navigation.
• Advantages:

  • Precise control of cursor.
  • Intuitive for most users.

• Disadvantages:

  • Requires a flat surface (mouse) or may cause fatigue (trackball).
  • Not ideal for users with limited hand mobility.

Remote Control

A handheld device that sends commands to a television, set‑top box, or other consumer electronics.

• Characteristics: Infrared (IR) or radio‑frequency (RF) transmission, limited button set, battery powered.
• Uses: Changing channels, adjusting volume, navigating menus on T \cdot s and media players.
• Advantages:

  • Convenient operation from a distance.
  • Simple interface.

• Disadvantages:

  • Line‑of‑sight required for IR.
  • Limited functionality compared with a full keyboard.

Joystick / Driving Wheel

Specialised pointing devices used mainly for gaming and simulation.

• Characteristics: Stick that pivots in multiple directions; may include buttons, throttle, or pedals.
• Uses: Flight simulators, racing games, CAD navigation.
• Advantages:

  • Provides realistic control for specific applications.
  • High precision for movement.

• Disadvantages:

  • Expensive and bulky.
  • Limited use outside specialised software.

Touch Screen (as an Input Device)

A display that detects the presence and location of a touch.

• Characteristics: Capacitive or resistive technology; supports single‑touch or multi‑touch gestures.
• Uses: Smartphones, tablets, kiosks, interactive whiteboards.
• Advantages:

  • Direct interaction – no separate pointing device.
  • Intuitive for many users.
  • Supports gestures (pinch‑zoom, swipe).

• Disadvantages:

  • Can be less accurate than a mouse for fine control.
  • Finger smudges reduce visibility.
  • Higher cost and potential durability issues.

Scanner

A device that converts physical documents or images into digital form.

• Characteristics: Flat‑bed or sheet‑fed; optical resolution measured in DPI.
• Uses: Archiving paperwork, digitising photos, OCR (optical character recognition).
• Advantages:

  • Creates exact digital copies.
  • Facilitates electronic storage and searching.

• Disadvantages:

  • Scanning can be time‑consuming for large volumes.
  • Quality depends on resolution and condition of original.

Camera (Webcam)

A digital camera that captures still images or video and sends the data to a computer.

• Characteristics: Built‑in or external; resolution measured in megapixels; may include built‑in microphone.
• Uses: Video conferencing, online learning, digital photography.
• Advantages:

  • Enables real‑time visual communication.
  • Simple to set up.

• Disadvantages:

  • Image quality varies with lighting and sensor size.
  • Privacy concerns if left active.

Microphone

A transducer that converts sound waves into electrical signals.

• Characteristics: Directional (cardioid, omnidirectional); analog or digital output.
• Uses: Voice recording, speech‑to‑text, online communication.
• Advantages:

  • Captures audio for a range of applications.
  • Can be integrated into headsets for hands‑free use.

• Disadvantages:

  • Background noise can affect quality.
  • Requires proper placement for optimal capture.

Sensors

Electronic components that detect physical phenomena and convert them into data.

• Common Types: Light sensors, temperature sensors, motion detectors, pressure sensors.
• Characteristics: Output may be analog voltage, digital signal, or serial data.
• Uses: Environmental monitoring, interactive installations, smart devices.
• Advantages:

  • Enable automated data collection.
  • Can trigger actions based on real‑world conditions.

• Disadvantages:

  • Calibration may be required.
  • Accuracy can be affected by external factors.

Light Pen

A hand‑held pointing device that detects light emitted from a CRT or LCD screen.

• Characteristics: Emits a light beam; works by detecting the screen’s refresh timing.
• Uses: Direct selection on screen, drawing, CAD work (historically).
• Advantages:

  • Provides precise point‑and‑click without a separate mouse.
  • Intuitive for drawing tasks.

• Disadvantages:

  • Limited to screens that support the technology (mostly obsolete).
  • Requires steady hand; can cause fatigue.

Summary Table