Input and Output Devices (Review and Extension)
How do I choose the right input or output device for a particular task?
- Classify hardware as input, output, both, or storage.
- Describe the purpose of common devices and their connection types.
- Select an appropriate device for a specified computing task and justify the choice.
Overview
You met input and output devices in detail in Term 1. This chapter is a short revision and extension: the focus here is on selection and justification — choosing the right device for a job and defending the choice on grounds of accuracy, speed, cost, durability and the PNG operating environment. Read the full Term 1 chapters first: 'Input Devices' and 'Output Devices'.
Quick recap
Input devices carry data into the system (keyboard, mouse, scanner, microphone, camera, barcode reader, sensor, touchscreen). Output devices present results (monitor, printer, projector, speaker, plotter). Some devices do both — a touchscreen, a modem, a headset, a multifunction printer.
Cross-links — read these Term 1 chapters for full coverage:
- Term 1 · Input Devices: Keyboards, pointing devices, scanners, sensors and specialised input.
- Term 1 · Output Devices: Display technology, printer types, projectors and audio output.
- Term 1 · Storage Devices & Media: Magnetic, optical and solid-state storage.
Selection criteria
When an exam asks you to 'recommend a device', judge it against these five criteria.
The five criteria:
- Accuracy: Does it capture data without transcription errors? A barcode reader beats typing.
- Speed: How much data per minute? A sheet-feed scanner beats a flatbed for 200 pages.
- Cost: Purchase price plus consumables — ink, toner, paper, replacement parts.
- Durability and environment: Dust, humidity and power fluctuation matter in many PNG schools.
- Accessibility: Can a student with low vision or limited mobility use it? Consider screen readers, large-print output and alternative pointing devices.
Connections
Most modern peripherals use USB (Type-A or Type-C), displays use HDMI, VGA or DisplayPort, and wireless devices use Bluetooth or Wi-Fi. When a device is not detected, checking the port, the cable and the driver — in that order — solves most cases.
Activity — Device recommendation brief
- Your school is setting up a records office and a design lab.
- For each of these tasks, recommend one input and one output device and justify each against the five selection criteria: (a) recording 800 student enrolment forms, (b) issuing report cards, (c) drawing school building plans, (d) delivering a lesson to a class of 40.
- Present your answers in a table: task · input device · output device · justification.
- Name three devices that are both input and output.
Reveal answer
Touchscreen, modem, headset (also multifunction printer, network card).
- Which device would you choose to enter 800 forms, and why?
Reveal answer
A sheet-feed scanner with OCR — it is far faster and avoids typing errors.
- What is the difference between hard copy and soft copy?
Reveal answer
Hard copy is permanent output on paper; soft copy is electronic output on a screen.
- Give one accessibility consideration when selecting output devices.
Reveal answer
A screen reader or large-print output for students with low vision.
Audit the peripherals in your computer lab. Record the make, connection type and condition of each, and recommend one replacement with justification.