Know and understand differences between input and output devices

ICT 0417 – Cambridge IGCSE/A‑Level Syllabus Notes

Learning Objective

Develop a thorough understanding of the key concepts, terminology and practical skills required across all 21 content sections of the Cambridge ICT (0417) specification, with particular emphasis on the differences between input and output devices.

1. Computer Systems Overview

1.1 Hardware

• CPU (Central Processing Unit) – the “brain” that executes instructions.
• RAM (Random‑Access Memory) – volatile memory for data while programmes run.
• ROM / Firmware – non‑volatile memory that stores permanent instructions (e.g., BIOS).
• Motherboard, bus, power supply, cooling system – platform that connects and powers all components.
• Storage hierarchy

  • Primary: RAM
  • Secondary: HDD, SSD, optical discs
  • Tertiary: Magnetic tape, cloud storage

1.2 Software

• System software – Operating System (OS) that manages hardware.

  • CLI – command‑line interface (text based).
  • GUI – graphical user interface (windows, icons, menus).

• Application software – programmes that perform specific tasks (e.g., word processor, spreadsheet, database).
• Utility software – anti‑virus, backup, disk‑defragmenter, compression tools.

1.3 Analogue vs Digital Data

1.4 Emerging Technologies (brief)

• Artificial Intelligence (AI) – machine learning, chatbots.
• Extended Reality (XR) – VR/AR head‑sets.
• Internet of Things (IoT) – networked sensors and smart devices.
• Quantum computing – early‑stage research with future impact.

2. Input Devices

Convert physical signals into digital data for the computer.

• Keyboard – alphanumeric entry; includes function keys, numeric keypad.
• Mouse / Touchpad – pointer control; optical or laser tracking.
• Scanner – optical character recognition (OCR) and image capture.
• Microphone – sound → digital audio (requires ADC).
• Digital Camera – still images & video; image sensor converts light to digital data.
• Joystick / Gamepad – directional control for games and simulations.
• Touchscreen – detects finger or stylus pressure (input) while also displaying output.
• Direct‑data‑entry devices

  • Magnetic‑stripe reader
  • RFID reader
  • Barcode scanner
  • Biometric fingerprint scanner

• Sensor devices – temperature, light, motion sensors used in IoT applications.

2.1 Comparison of Input Devices

3. Output Devices

Present processed data to the user in a usable form.

• Monitor / Display – visual output; LCD, LED, OLED, or CRT. Resolution (e.g., 1920×1080) and colour depth (e.g., 24‑bit) are key specifications.
• Printer – hard‑copy of text or graphics.

  • Ink‑jet – good for colour photos.
  • Laser – fast, high‑quality text.

• Speakers / Headphones – audio output; convert digital samples to analogue sound via DAC.
• Projector – enlarges visual output for groups.
• Plotter – high‑precision line drawing, used in engineering and CAD.
• Haptic devices – vibration or force feedback (e.g., game controllers, VR gloves).
• LED/LCD signage – public‑information displays.

3.1 Comparison of Output Devices

4. Combined Input/Output Devices

• Touchscreen – display (output) + touch detection (input).
• All‑in‑One printer – scanner (input) + printer (output).
• Interactive whiteboard – shows presentations (output) and detects pen/finger gestures (input).
• Smartphone – touch screen, camera (input) and speaker, display (output).

5. Storage Devices & Media

5.1 Magnetic Storage

• Hard Disk Drive (HDD) – rotating platters, magnetic heads; high capacity, slower random access.
• Floppy Disk / Zip Disk – legacy portable media, low capacity.
• Magnetic Tape – archival storage; sequential access, very high capacity.

5.2 Optical Storage

• CD‑R / CD‑RW – 700 MB, read‑once or rewrite.
• DVD‑R / DVD‑RW – 4.7 GB per layer.
• Blu‑ray Disc – 25 GB per layer, high‑definition video.

5.3 Solid‑State & Flash Storage

• Solid‑State Drive (SSD) – no moving parts, very fast random access.
• USB flash drive / Memory card – portable, removable.
• eMMC / NVMe – embedded flash used in tablets and high‑performance laptops.

5.4 Cloud & Network Storage

• Cloud services – remote servers accessed via the Internet (e.g., Google Drive, OneDrive).
• Advantages: accessibility from any device, automatic backup, collaborative editing.
• Considerations: bandwidth, security, subscription cost.

5.5 Comparison of Storage Types

6. Networks & Their Effects

6.1 Basic Network Components

• Network Interface Card (NIC) – connects a computer to a network.
• Router – forwards data between networks; provides NAT, DHCP and firewall functions.
• Switch – connects multiple devices within a LAN; directs traffic using MAC addresses.
• Access Point (AP) – provides Wi‑Fi connectivity.
• Modem – converts digital data to analogue signals for telephone/DSL lines.

6.2 Types of Networks

• LAN (Local Area Network) – confined to a building or campus; high speed.
• WAN (Wide Area Network) – spans cities or countries; uses public infrastructure.
• Internet – global WAN providing access to web services.
• Wireless technologies – Wi‑Fi (IEEE 802.11), Bluetooth, NFC, Zigbee.

6.3 Network Effects

• Collaboration – shared documents, video conferencing, real‑time editing.
• Cloud computing – SaaS, IaaS, PaaS models.
• Security risks – unauthorised access, malware, phishing, ransomware.
• Digital divide – unequal access to high‑speed Internet.

6.4 Simple Network Diagram (textual)

Computer → NIC → Switch → Router → Internet → Web Server

7. Effects of Using IT

7.1 Health Effects

• Repetitive‑strain injury (RSI) – use ergonomic keyboards, take regular breaks.
• Eye strain – 20‑20‑20 rule, proper lighting, anti‑glare screens.
• Posture problems – adjustable chair, monitor at eye level.

7.2 Environmental & Social Effects

• E‑waste – disposal of obsolete hardware; importance of recycling programmes.
• Energy consumption – power‑saving settings, use of energy‑efficient devices.
• Digital divide – socioeconomic gaps in access to technology.
• Ethical use – respecting privacy, avoiding plagiarism, responsible online behaviour.

8. ICT Applications

For each application area a typical software tool and an exam‑style example are given.

• Communication – email (Outlook), instant messaging (WhatsApp), video calls (Zoom). Example: Draft a professional email requesting a meeting.
• Modelling & Simulation – CAD (AutoCAD), GIS (ArcGIS), virtual labs. Example: Produce a 3‑D model of a simple bridge.
• Banking & Finance – online banking portals, spreadsheet budgeting. Example: Calculate interest on a savings account using a spreadsheet.
• Education – e‑learning platforms (Moodle), virtual classrooms. Example: Upload a presentation to a school intranet.
• Healthcare – electronic patient records, tele‑medicine apps. Example: Record a patient’s vital signs using a digital form.
• Retail & Logistics – barcode scanning, inventory management systems. Example: Generate a stock‑take report after scanning items.
• Expert Systems – decision‑support software, AI chatbots. Example: Use a troubleshooting wizard to diagnose a printer fault.
• Recognition Systems – facial recognition, voice recognition. Example: Set up a fingerprint login on a laptop.
• School Management – timetabling software, attendance systems. Example: Produce a weekly timetable for Year 10.
• Booking Systems – online reservation for rooms, tickets. Example: Book a laboratory session via a web portal.

9. Systems Life‑Cycle (SLC)

Cambridge uses a five‑stage model.

1. Analysis – gather user requirements, produce a requirements specification.
2. Design – create flowcharts, pseudo‑code, UI mock‑ups, database schema.
3. Testing – develop test plans, run trial data, record results, correct errors.
4. Implementation – install hardware/software, train users, migrate data.
5. Documentation & Evaluation – produce user manuals, technical documentation, evaluate against criteria (efficiency, usability, suitability).

Key Artefacts

• Requirements specification
• Flowchart / algorithm
• Database design (tables, primary/foreign keys)
• Test plan & test data
• User manual / help file
• Technical documentation (hardware, software configuration)
• Evaluation report (strengths, weaknesses, recommendations)

10. Safety & Security

10.1 Physical Safety

10.2 E‑Safety & Data Protection

• Strong passwords – at least 8 characters, mix of upper‑/lower‑case letters, numbers, symbols.
• Two‑factor authentication (2FA) – adds a second verification step.
• Regular updates & patches – keep OS and applications current.
• Anti‑malware software – real‑time scanning, scheduled scans.
• Backup strategy – 3‑2‑1 rule – three copies, on two different media, one off‑site (e.g., cloud).
• Encryption – protect files (AES) and communications (SSL/TLS).
• Data‑protection legislation – GDPR (EU), Data Protection Act (UK); principles of consent, purpose limitation, data minimisation.

10.3 Common Threats & Counter‑measures

11. Audience & Copyright

11.1 Audience Analysis

• Identify age, prior knowledge, interests, and any accessibility requirements.
• Choose language level, visual aids, and examples appropriate to the audience.
• Consider cultural relevance and inclusive design.

11.2 Copyright & Software Piracy

• Copyright basics – protects original literary, artistic, musical, and software works.
• Unauthorised copying, distribution or modification is illegal.
• Software piracy – installing or using unlicensed copies; penalties include fines and imprisonment.
• Protection methods: product keys, digital licences, hardware dongles, online activation, watermarking.
• Fair‑use exceptions for education are limited; always seek permission or use open‑source alternatives.

12. Communication (Email & Internet)

12.1 Email

• Structure: To, CC, BCC, Subject, Salutation, Body, Closing, Signature.
• Netiquette – clear subject, concise language, professional tone, avoid ALL‑CAPS.
• Attachments – keep size reasonable, use common formats (PDF, DOCX, JPG).
• Spam filters – recognise phishing attempts.

12.2 Effective Use of the Internet

• WWW vs Intranet/Extranet – public web vs private organisational networks.
• URL structure – protocol (http/https), domain name, path, file name.
• Key protocols – HTTP/HTTPS (web), FTP (file transfer), SMTP/POP3/IMAP (email).
• Search‑engine techniques – use keywords, Boolean operators (AND, OR, NOT), filters.
• Evaluating information – authority, accuracy, bias, currency, relevance.
• Internet risks – malware, identity theft, cyber‑bullying; use firewalls and safe browsing settings.

13. File Management

• Folder hierarchy – logical structure (e.g., Year 10 → Science → Lab Reports).
• File naming conventions – avoid spaces, use dates (YYYYMMDD), version numbers (v01, v02).
• File extensions – .docx, .xlsx, .pdf, .jpg, .png, .zip.
• File compression – ZIP or RAR to reduce size for transfer.
• Backup strategies – 3‑2‑1 rule, use external drives or cloud services.
• Permissions – read, write, execute; set appropriately for shared folders.

14. Working with Images

• Resolution – measured in DPI (dots per inch) or PPI (pixels per inch); higher resolution = better print quality.
• Colour depth – 1‑bit (black/white), 8‑bit (256 colours), 24‑bit (true colour), 32‑bit (includes alpha channel).
• File formats

  • Raster: JPEG (lossy, good for photos), PNG (lossless, supports transparency), GIF (animation, limited colours).
  • Vector: SVG, EPS – scalable without loss of quality.

• Basic editing tasks – crop, resize, rotate, adjust brightness/contrast, add text.
• Use in documents – maintain appropriate resolution (150 dpi for screen, 300 dpi for print).

15. Layout and Styles

• Fonts – typeface, size, style (bold, italic); use headings (Heading 1, Heading 2) for hierarchy.
• Paragraph styles – alignment, line spacing, indentation, bullet/numbered lists.
• Templates – pre‑designed page layouts for consistency.
• CSS basics (for web authoring)

  • Selectors, properties, values (e.g., p {margin‑bottom:10px;}).
  • External stylesheet vs internal style block.

16. Proofreading & Validation

• Spell‑check & grammar tools – built‑in or external plugins.
• Data validation – restrict entry type (numeric, date), set ranges, use drop‑down lists.
• Review techniques – read aloud, peer review, check formatting consistency.

17. Graphs and Charts

• Common types – bar chart, column chart, line graph, pie chart, scatter plot.
• Key components – title, axis labels, units, scale, legend, data markers.
• Design tips – avoid 3‑D effects that distort data, use appropriate colours, keep labels legible.
• Creating in software – select data range, choose chart type, customise elements, add data labels.

18. Document Production (Word Processing)

• Creating, saving and printing documents.
• Formatting text – fonts, size, colour, bold/italic/underline.
• Paragraph formatting – alignment, line spacing, indentation, borders.
• Inserting tables, images, headers/footers, page numbers.
• Using styles and templates for consistent layout.
• Mail merge – generate personalised letters from a data source.

19. Databases

• Structure – tables, fields (columns), records (rows).
• Primary key – unique identifier for each record.
• Foreign key – links related tables.
• Forms – data entry screens; validation rules can be applied.
• Queries – retrieve specific data using criteria (SELECT, WHERE).
• Reports – formatted output of query results, can include totals and charts.

20. Presentations

• Creating slides, applying a consistent theme.
• Inserting text, images, audio, video, and animations.
• Using slide transitions and object animations sparingly for impact.
• Presenter view – notes, timer, preview of next slide.
• Export options – PDF, video, or PowerPoint file.

21. Spreadsheets

• Worksheets, cells, rows, columns.
• Entering data – text, numbers, dates.
• Formulas & functions

  • Arithmetic: =A1+B1
  • SUM, AVERAGE, MIN, MAX
  • IF, VLOOKUP/HLOOKUP, COUNTIF

• Cell referencing – relative, absolute (\$A\$1).
• Data validation – drop‑down lists, numeric limits.
• Conditional formatting – highlight cells based on criteria.
• Creating charts from data ranges.
• Sorting and filtering data.

22. Website Authoring

• HTML basics

  • Structure: <!DOCTYPE html>, <html>, <head>, <body>
  • Common tags: <h1>–<h6>, <p>, <a href="...">, <img src="..." alt="...">, <ul>/<ol>, <table>.

• CSS basics – selectors, properties (colour, margin, padding), linking external stylesheet with <link rel="stylesheet" href="style.css">.
• Hyperlinks – internal (anchor) and external links, opening in new window (target="_blank").
• Accessibility – alt text for images, sufficient colour contrast, logical heading order.
• Testing – view in multiple browsers, check responsiveness on mobile devices.

23. Revision Checklist (Exam‑Style)

1. Can you list at least three input devices and explain how they convert analogue signals to digital data?
2. Can you compare the main functions of a monitor and a printer, and give an example where each is the preferred output?
3. Do you know the five phases of the Systems Life‑Cycle and the key artefacts produced at each stage?
4. Are you able to identify common security threats and match each with an appropriate counter‑measure?
5. Can you create a simple database table, define a primary key, and write a basic query to retrieve records?
6. Can you design a short website page using correct HTML tags and a linked CSS stylesheet?

Use these notes as a concise reference while studying for the Cambridge IGCSE/A‑Level ICT (0417) examination. They cover every mandatory sub‑topic, include examples, and provide quick‑look tables for comparison and revision.