Comprehensive Study Notes on Information and Communication Technology

Resources and Assessment Structure in Information and Communication Technology

Series Components

The Cambridge IGCSE™ Information and Communication Technology series is designed for the $0417/0983$ syllabus. The series consists of:

• Student’s Book: Third Edition (ISBN: $9781398318540$).

• Boost eBook: Digital version (ISBN: $9781398320932$).

• Practical Workbook: Second Edition (ISBN: $9781398318519$).

• Theory Workbook: Second Edition (ISBN: $9781398318564$).

• Teacher’s Guide with Boost Subscription: Includes a print handbook and online resources (ISBN: $9781398318533$).

Assessment for Examination from $2023$

There are three primary examination papers:

• Paper $1$ (Theory):

  • Duration: $1\,hour\,30\,minutes$.

  • Total Marks: $80$.

  • Coverage: Syllabus sections $1$ to $21$.

• Paper $2$ (Document Production, Databases and Presentations):

  • Duration: $2\,hours\,15\,minutes$.

  • Total Marks: $70$.

  • Coverage: Syllabus sections $11$ to $16$, $17$, $18$, and $19$.

• Paper $3$ (Spreadsheets and Website Authoring):

  • Duration: $2\,hours\,15\,minutes$.

  • Total Marks: $70$.

  • Coverage: Syllabus sections $11$ to $16$, $20$, and $21$.

Concepts of Hardware and Software

Definitions and Analogies

• Hardware: The physical components of a computer system. An analogy is the physical pages and ink of a book.

• Software: The programs that control the system and process data. An analogy is the words written on the pages of a book; without them, the hardware is useless.

Categories of Hardware

Hardware is divided into external and internal components.

• External Hardware:

  • Input Devices: Keyboard, mouse, camera, microphone, sensor, and scanner.

  • Output Devices: Monitor, printer, speakers, projector, and plotter.

• Internal Hardware:

  • Motherboard: A printed circuit board made of non-conductive plastic with copper or aluminium circuits. It acts as a hub connecting all components.

  • Central Processing Unit (CPU): An electronic circuit board that executes program instructions. It consists of the Arithmetic and Logic Unit (ALU) for calculations and the Control Unit (CU) for decoding and executing instructions.

  • Graphics Card: Connects to the motherboard to send graphical info to displays. Contains its own processing unit, RAM, and a cooling heat sink.

  • Sound Card: Provides the ability to produce sound through speakers/headphones and record sound via a microphone.

  • Network Interface Card (NIC): Allows a device to connect to a network. Each NIC has a unique, hard-coded Media Access Control (MAC) address.

  • Random Access Memory (RAM): Internal chip for temporary storage of data/applications currently in use. It is volatile, meaning data is lost when power is off.

  • Read-Only Memory (ROM): Used for permanent data like configuration and the BIOS (Basic Input/Output System). It is non-volatile.

  • Internal Storage (HDD/SSD): Hard Disk Drives (magnetic) and Solid-State Drives (flash technology) used for storing the OS, files, and applications.

Categorization of Software

Application Software

Programs designed for specific user tasks:

• Word Processing: Used for text manipulation (essays, reports). Features include spell checkers, thesaurus, and importing images.

• Spreadsheet: Organizes numerical data in a grid of lettered columns and numbered rows (e.g., cell $B6$). Supports formulae, graphing, and "what-if" modelling.

• Database Management System (DBMS): Organizes data in tables with records (rows) and fields (columns). Features include queries and reporting.

• Control and Measurement: Interfaces with sensors to measure physical quantities (temperature) or control processes (opening valves).

• Audio/Video Editing: Allows manipulation of tracks, length, volume, transitions, and colour correction.

• Computer-Aided Design (CAD): Helps create and analyze $2D$ or $3D$ designs. Can rotate drawings and estimate costs.

• Apps and Applets: Applets are small single-task applications (often embedded in HTML). Apps are substantial programs for mobile devices.

System Software

Programs that allow hardware to run and provide a platform for application software:

• Compiler: Translates high-level language (Java, Python, C++) source code into machine-readable object code.

• Linker: Combines multiple object files (modules) into a single executable program.

• Device Driver: Software allowing hardware (printers, mice) to communicate with the OS.

• Operating System (OS): Background software managing I/O operations, error handling, security, and the user interface.

• Utilities: Manage and maintain resources, such as anti-virus, disk repair, file management, and defragmenters.

Data Types and Main Components

Analogue vs. Digital

• Digital Data: Binary format (base $2$) using values $0$ and $1$. It consists of discrete, discontinuous values.

• Analogue Data: Physical data that changes smoothly between values (e.g., $2.5$, $4.652$) rather than in steps.

• Conversion: Hardware uses an Analogue to Digital Converter (ADC) for input and a Digital to Analogue Converter (DAC) for computer-controlled outputs (like motors).

Internal Memory Details

• BIOS: Stored in ROM, it tells the computer how to start up and performs hardware checks.

• CMOS: A battery-powered chip that stores date, time, and system configuration.

• Backing Storage: Non-volatile storage like HDD/SSD used for permanent file storage. It is not directly addressable by the CPU (data must move to RAM first).

Operating Systems and User Interfaces

User Interface Types

• Command Line Interface (CLI): Requires typing specific, formatted commands. Used by technicians for direct communication with the computer. It is low-memory but slow and error-prone.

• Graphical User Interface (GUI): Uses pictures (icons) and symbols. Commonly uses WIMP (Windows, Icons, Menu, Pointing device). It is user-friendly but memory-intensive.

• Dialogue-Based: Uses voice activation (e.g., Siri, Alexa, Cortana). Useful for hands-free operations in cars or for people with disabilities.

• Gesture-Based: Uses sensors/cameras to track head, hand, or foot movements (e.g., rotating a finger to adjust car volume). No physical contact is required.

Comparison of Computer Types

Desktop vs. Laptop

• Desktop: Non-portable, separate components. Advantages: standardized parts, cheaper upgrades, better specification for price, stable wired internet, better heat dissipation.

• Laptop: Integrated monitor/keyboard/CPU. Advantages: portability, lack of trailing wires, lightweight. Disadvantages: easier to steal, limited battery life, awkward input devices.

Mobile Devices

• Smartphones: Use OS (iOS, Android) for apps, email, and media. Use OLED screens and various sensors (accelerometer, proximity).

• Tablets: Touch-screen technology with virtual keyboards. Fast boot time and long battery life compared to laptops.

• Phablets: Hybrid devices with screen sizes between $5.1$ inches ($13\,cm$) and $7$ inches ($18\,cm$).

• Connectivity: Devices use Wi-Fi or $3G/4G/5G$ networks. Li-Fi is an emerging technology using visible light for faster, more secure communication.

Emerging Technologies

Artificial Intelligence (AI)

Machines carrying out tasks requiring intelligence (language, facial recognition, prediction).

• Isaac Asimov’s Laws of Robotics:

  1. Robots may not injure a human.

  2. Robots must obey humans.

  3. Robots must protect themselves (unless conflicting with Laws $1$ or $2$).

• Impact: Positive (bomb disposal, surgical research) vs. Negative (job losses in manufacturing and transport, loss of human skills).

Extended Reality (XR)

• Augmented Reality (AR): Virtual objects are overlaid on the physical world (e.g., Pokémon GO). Used in retail for trying on makeup or medical diagnosis (Echopixel).

• Virtual Reality (VR): Fully immersive simulated environment using headsets for a $360^{\circ}$ view. Used for military training, education (exploring Stonehenge), and engineering.

Technical Command Words

• Analyse: Examine in detail to show meaning.

• Compare: Identify similarities and differences.

• Contrast: Identify differences.

• Define: Give precise meaning.

• Demonstrate: Show or give an example.

• Describe: State points/main features.

• Discuss: Write in-depth in a structured way.

• Evaluate: Judge the quality or importance.

• Explain: Provide why/how with evidence.

• Give: Produce an answer from source or memory.

• Identify: Name or select.

• Justify: Support a case with evidence/argument.

• State: Express in clear terms.

• Suggest: Apply knowledge to make proposals.