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

• Standard QWERTY layout – 101‑104 keys (incl. function keys F1‑F12)
• Mechanical, membrane or scissor‑type switches; key‑travel 1.5‑2 mm (mechanical) or 0.8‑1.2 mm (membrane)
• Key‑rollover & anti‑ghosting (typically 6‑key rollover)
• Back‑lighting (white or RGB) on many models
• Modifier keys (Shift, Ctrl, Alt, Windows/Command) and optional numeric keypad
• Ergonomic variants: split, curved, low‑profile, tactile feedback
• On‑screen keyboards for touch devices and assistive technology

• Fast, accurate alphanumeric input.
• Universal – supported by all software.
• Low cost, durable, widely available.
• Ergonomic designs reduce strain.

• Requires hand‑eye coordination; not ideal for users with limited hand mobility.
• Risk of repetitive‑strain injury (RSI) if posture is poor.
• Limited for drawing or gesture‑based input.

• Keep wrists straight; use a wrist rest or ergonomic split keyboard.
• On‑screen keyboards aid users with motor impairments.
• No specific e‑safety issues, but keep firmware updated for wireless models.

• 10 digit keys + “.”, “+”, “‑”, “*”, “/” and “Num Lock”.
• Usually on the right side of a full‑size keyboard; detachable modules exist for laptops.
• Key‑travel similar to main keyboard; may include tactile “click” feedback.

• Speeds numeric entry compared with the alphanumeric section.
• Reduces finger movement – less fatigue for repetitive number work.

• Increases overall keyboard width; not useful for text‑only tasks.
• Often omitted on compact laptops – users must use the top‑row numbers.

• Ergonomic when used with a proper wrist position; consider a separate external keypad for laptops.
• No specific e‑safety concerns.

• Mouse – optical or laser; DPI range 400‑3200; wired (USB) or wireless (RF/BLE); may have scroll wheel, side buttons.
• Touchpad (trackpad) – multi‑finger gestures (tap, pinch‑zoom, two‑finger scroll); integrated on laptops.
• Trackball – stationary ball, rolled with thumb or fingers; useful where desk space is limited.
• Graphics tablet (digitiser) – pressure‑sensitive pen (2048‑8192 levels); active area 6‑12 inches.
• Stylus – used with touch‑screen tablets or graphics tablets; may have tilt‑sensing.

• Precise two‑dimensional control.
• Intuitive for most users; gestures increase productivity.
• Wireless models reduce desk clutter.

• Mouse needs a flat surface; trackball can cause finger fatigue.
• Graphics tablets require calibration and learning curve.

• Use a mouse pad to reduce wrist strain; ergonomic mice (vertical, trackball) help users with RSI.
• Touchpads support accessibility features such as “Tap to click”.
• Wireless devices must be turned off when not in use to avoid accidental data capture.

• Hand‑held, typically IR (line‑of‑sight) or RF (2.4 GHz) transmission.
• 10‑30 buttons; may include numeric keypad for channel entry.
• Battery powered (AA/AAA) or rechargeable.

• Convenient operation from a distance.
• Simple, familiar layout.

• IR models need direct line‑of‑sight.
• Limited functionality compared with a full keyboard or mouse.

• Large‑button designs aid users with reduced dexterity.
• RF models avoid line‑of‑sight issues but may interfere with other wireless devices.

• Multi‑axis stick (X, Y, Z rotation); may include throttle, pedals, programmable buttons.
• USB or Bluetooth connection; force‑feedback optional.

• Realistic, high‑precision control for specialised applications.
• Simultaneous control of several parameters (steering + throttle).

• Relatively expensive and bulky.
• Limited usefulness outside gaming or simulation.

• Adjustable hand grips reduce fatigue; suitable for users with limited wrist movement.
• Secure mounting prevents accidental falls.

• Capacitive (most common) or resistive technology.
• Single‑touch or multi‑touch (up to 10‑point) gestures.
• Integrated with display (smartphones, tablets) or added to monitors.

• Direct interaction – no separate pointing device.
• Highly intuitive for children and non‑technical users.
• Supports pinch‑zoom, swipe, rotate.

• Less precise than a mouse for fine graphic work.
• Finger smudges reduce visibility; regular cleaning required.
• Higher cost; resistive screens are less durable.

• Adjust screen brightness to avoid eye strain.
• Screen‑reader software provides accessibility for visually impaired users.
• e‑Safety: disable touch input when not needed to prevent accidental actions.

• Flat‑bed or sheet‑fed; optical resolution 300‑1200 DPI; colour depth 24‑48 bits.
• Automatic Document Feeder (ADF) for batch scanning.
• USB or network (Wi‑Fi/Ethernet) connectivity.

• Creates exact digital copies of physical media.
• Facilitates electronic storage, searching and sharing.
• Higher DPI yields better quality for printing or enlargement.

• Scanning large volumes can be time‑consuming.
• Image quality depends on resolution, colour depth and condition of original.
• Sheet‑fed models may jam with thick or folded paper.

• Keep the scanner lid closed when not in use to avoid dust exposure.
• Use OCR software with accessibility options (e.g., screen‑reader compatible output).
• e‑Safety: ensure scanned documents containing personal data are stored securely.

• Built‑in or external USB; resolution 720p‑4K; frame rate 30‑60 fps.
• May include built‑in microphone and privacy shutter.

• Enables real‑time visual communication.
• Plug‑and‑play on most computers.
• Supports facial‑recognition login on some systems.

• Image quality highly dependent on lighting and sensor size.
• Privacy risk if left active or compromised.
• External webcams add cost and need mounting.

• Use a privacy cover or software toggle when not in use.
• Adjust lighting to reduce eye strain for both user and remote participants.
• Accessible placement (adjustable stand) aids users with limited neck mobility.

• Directional patterns: cardioid, omnidirectional, bidirectional.
• Analog (3.5 mm jack) or digital (USB); built‑in to headsets, laptops or stand‑alone.
• Frequency response 20 Hz‑20 kHz (typical); sample rate 44.1 kHz‑96 kHz.

• Captures clear audio for many applications.
• Headset versions allow hands‑free operation.

• Background noise can degrade quality; may need pop filter or acoustic treatment.
• Proper placement (distance & angle) essential for optimal capture.

• Use a pop filter to reduce plosive sounds.
• Position microphone away from computer fans to avoid unwanted noise.
• e‑Safety: mute microphone when not speaking to protect privacy.

• Types: Light (photo‑resistor, photodiode), Temperature (thermistor, RTD), Motion (PIR, accelerometer), Pressure, Proximity, Humidity, Magnetic (Hall effect).
• Outputs: analog voltage/current, digital (I²C, SPI, UART) or serial data.
• Often require calibration and may be interfaced via microcontroller or USB data‑logger.

• Enables automated, real‑time data collection from the physical world.
• Can trigger actions (e.g., turn lights on when motion is detected).

• Accuracy may be affected by external factors (temperature drift, ambient light).
• Calibration and periodic maintenance often required.

• Secure mounting to prevent accidental dislodgement.
• Use shielding or filtering to reduce electrical noise.
• Data privacy: ensure sensor data containing personal information is stored securely.

• Hand‑held device that emits a light beam; detects CRT or early LCD refresh timing to locate position.
• Works mainly with CRT monitors; limited modern support.

• Precise point‑and‑click without a separate mouse.
• Intuitive for drawing or annotating directly on screen.

• Obsolete for most modern flat‑panel displays.
• Requires a steady hand; can cause fatigue during prolonged use.

• Not recommended for users with tremor or limited hand control.
• e‑Safety: no specific concerns, but ensure the pen tip is not damaged.

• Reads magnetic data on 3 tracks; up to 79 characters per track.
• USB or serial interface; swipe or dip mode.

• Fast, contact‑less reading.
• Widely supported by commercial software.

• Limited data capacity.
• Stripe can be demagnetised or wear out.

• Position the reader at a comfortable height to avoid bending.
• Secure card data; comply with GDPR when storing personal information.

• Reads passive or active RFID tags; LF (125 kHz), HF (13.56 MHz) or UHF (860‑960 MHz).
• No line‑of‑sight required; can read multiple tags simultaneously.

• Durable tags survive harsh environments.
• Fast batch reading.

• Higher initial cost than magnetic‑stripe readers.
• Potential privacy concerns if tags are read without consent.

• Mount reader at waist height to reduce bending.
• Encrypt tag data where possible to protect privacy.

• Detects marks (bubbles, checkboxes) or printed characters.
• Specialised software interprets data; often integrated with flat‑bed scanners.

• Rapid conversion of large numbers of paper forms.
• Reduces manual transcription errors.

• Requires high‑quality printing and consistent mark placement.
• Software licences can be costly.

• Ensure good lighting and clean scanner glass for accurate detection.
• Provide clear instructions for users with visual impairments (e.g., tactile marks).

• Laser (1‑D) or imaging sensor (2‑D) scanner.
• Handheld or integrated into POS terminals; USB or Bluetooth.

• Instant reading of product information.
• Supports both 1‑D barcodes and 2‑D QR codes.

• Scanning may fail with damaged or poorly printed codes.
• Laser scanners require eye‑safety precautions.

• Position scanner at a comfortable height; avoid repetitive bending.
• Secure data transmission (e.g., use encrypted Bluetooth).

• Reads EMV chip cards; contacts the chip via a metal pad.
• USB or serial interface; may include PIN‑pad for secure entry.

• Higher security than magnetic‑stripe cards.
• PIN entry on device reduces risk of password interception.

• More expensive hardware.
• Requires regular firmware updates to stay compliant with security standards.

• Place PIN‑pad at a comfortable height; use tactile keys for visually impaired users.
• Encrypt transaction data to meet PCI‑DSS requirements.

• Near‑field communication (13.56 MHz); reads/writes to NFC tags or smartphones.
• Range ≤ 10 cm; USB or built‑in to mobile devices.

• Very quick, tap‑to‑interact operation.
• No physical wear on tags.

• Limited to short range; may interfere with other RF devices.
• Security concerns if tags are not encrypted.

• Position reader at waist or chest height for easy tapping.
• Educate users about not sharing NFC‑enabled cards with strangers.

• Reads ISO/IEC 7816 contact cards and ISO/IEC 14443 contactless cards.
• USB, PCIe or embedded module; may support multiple card formats.

• Supports a wide range of applications (authentication, data storage).
• Contactless mode reduces wear on card contacts.

• Initial cost higher than simple magnetic‑stripe readers.
• Requires management of card issuance and revocation.

• Mount at an ergonomic height; provide tactile guides for blind users.
• Encrypt card data and follow data‑protection regulations.

• LCD, LED or OLED; sizes 19‑32 in.; native resolution 1080p‑4K.
• Refresh rate 60‑144 Hz; response time 1‑5 ms.
• Connectors: HDMI, DisplayPort, VGA (legacy), USB‑C.

• High‑resolution images and text.
• Adjustable brightness/contrast for eye comfort.

• Screen glare can cause eye strain.
• Large monitors take up desk space.

• Position top of screen at eye level; keep ~50‑70 cm distance.
• Use anti‑glare filters or matte screens for accessibility.
• e‑Safety: enable screen‑lock and power‑saving mode.

• Same characteristics as input section; plus backlight for visibility.
• Resolution typically 1920×1080 or higher.

• Provides visual feedback directly under the finger.
• Supports dynamic UI changes (e.g., menus, animations).

• Higher cost than non‑touch monitors.
• Potential for smudges and reduced readability in bright environments.

• Adjust screen brightness to avoid eye strain.
• Screen‑reader compatibility for visually impaired users.
• e‑Safety: disable touch input when not needed to prevent accidental actions.

• LCD or DLP; brightness 2000‑5000 lumens; native resolution 720p‑1080p.
• Connectivity: HDMI, VGA, USB, wireless (Wi‑Fi/Miracast).

• Displays content to a large audience.
• Portable models enable flexible use.

• Requires a darkened room for optimal image quality.
• Bulb life limited; replacement cost.

• Set up at a comfortable viewing height; use a stable mount.
• Adjust focus and keystone to reduce eye strain.
• e‑Safety: ensure proper ventilation to avoid overheating.

• Monochrome or colour; resolution 600‑1200 dpi; print speed 20‑40 ppm.
• Uses toner cartridges; network (Ethernet) or USB connectivity.

• Fast, high‑quality text and graphics.
• Low cost per page for black‑and‑white output.

• Higher upfront cost than ink‑jet.
• Toner can be messy if mishandled.

• Place printer at a comfortable height to avoid bending.
• Use toner‑safe disposal containers for environmental safety.

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