A/L ICT short notes — every unit, one line per objective

1.1 Data, information and their life cycle

• ·Define data and information and distinguish clearly between them, with an example
• ·List the stages of the data life cycle: creation, management, removal of obsolete data
• ·State the characteristics of valuable information (timely, accurate, in context, understandable, low uncertainty)

1.2 Why technology is needed to create, disseminate and manage information

• ·Explain the drawbacks of manual data processing (errors, duplication, delay, poor sharing)
• ·Describe how networks, the Internet, mobile computing and cloud computing overcame those drawbacks
• ·Give examples of information used in decision making, policy making, prediction, planning and monitoring

1.3 Abstract model of information creation

• ·Draw and label the input-process-output (IPO) abstract model
• ·Relate the IPO model to a computer system and to the general definition of a system

1.4 Hardware, software and human components of a computer system

• ·Classify the hardware and software components of a computer system
• ·Distinguish proprietary from open-source software, with an advantage and disadvantage of each

1.5 Data processing activities

• ·List and describe the five data-processing steps: gathering, validation, processing, output, storage
• ·Identify data-gathering tools (OMR, OCR, MICR, card/tape readers, barcode readers, sensors) and validation methods (type/presence/range checks)
• ·Distinguish batch vs real-time processing, online vs offline input, and local vs cloud storage

1.6 Application of ICT across domains

• ·Identify the ICT tools and skills used in education, healthcare, agriculture, business, engineering, tourism, media and law enforcement
• ·Discuss, in depth, the benefit ICT brings to at least two named domains

1.7 Impact of ICT on society

• ·Explain the social and economic benefits of ICT
• ·Explain the social, economic, environmental, ethical, legal and privacy issues caused by ICT — piracy, phishing, copyright, plagiarism, licensing, digital divide, e-waste
• ·Relate ICT's role to the Sustainable Development Goals and to closing the digital divide

2.1 Evolution and classification of computers

• ·Describe generations 1G-4G of computers with their defining technology and features, in tabular form
• ·Classify computers by technology (analog/digital), purpose (general/special) and size (super/mainframe/mini/micro, incl. mobile devices)

2.2 Hardware components and their interfaces

• ·Identify input devices, distinguishing direct-entry from keyboard-entry, and their interfaces
• ·Identify output devices and their features (CRT/TFT/LED monitors, dot-matrix/inkjet/laser/3D printers, plotters)
• ·Categorise storage devices and state the advantages of direct-entry input over keyboard-entry input

2.3 Von-Neumann architecture and the fetch-execute cycle

• ·Draw and label the Von-Neumann architecture (CU, ALU, memory, I/O, data and control buses)
• ·Describe the stored-program concept and the fetch-execute cycle
• ·Explain why multi-core processors are needed

2.4 Memory hierarchy and PC memory system

• ·Explain the need for a memory hierarchy and its comparison criteria (access time, capacity, cost)
• ·Compare volatile memory (registers, cache, RAM incl. SRAM/DRAM/SDRAM) and non-volatile memory (ROM/PROM/EPROM/EEPROM, secondary storage)
• ·Compare memory types by access time, cost per MB, capacity and physical arrangement of data

3.1 Number systems and representation of numbers

• ·Convert between decimal, binary, octal and hexadecimal in both directions
• ·Represent signed integers using signed-magnitude, one's complement and two's complement
• ·Explain the role of the MSB as a sign bit and why two's complement is preferred for arithmetic

3.2 Character representation

• ·List character-encoding schemes: BCD, EBCDIC, ASCII, Unicode
• ·Convert a given symbol or string into a stated encoding scheme
• ·State an advantage/disadvantage of each scheme (e.g. ASCII's limited range vs Unicode's multilingual support)

3.3 Binary arithmetic and bitwise logic operations

• ·Add and subtract multi-digit binary integers, with carry/borrow shown
• ·Perform bitwise NOT, AND, OR and XOR operations on binary numbers

4.1 Basic and universal logic gates

• ·Name and draw the symbols of NOT, AND, OR, XOR, NAND, NOR and XNOR gates
• ·Construct truth tables for basic and combinational gates, up to three inputs
• ·Explain why NAND/NOR are universal gates and build a given gate using only NAND/NOR

4.2 Boolean algebra and Karnaugh map simplification

• ·State and apply Boolean postulates/laws: commutative, associative, distributive, identity, redundancy, De Morgan's
• ·Convert a truth table to SOP/POS form and transform between SOP and POS
• ·Simplify Boolean expressions using theorems and using a Karnaugh map

4.3 Designing simple digital circuits

• ·Derive a logic expression and truth table from a stated real-world requirement, up to three inputs
• ·Draw the resulting digital circuit using logic gates

4.4 Combinational and sequential circuits in the CPU

• ·Derive the truth table and logic expression for a half adder and a full adder
• ·Explain how a flip-flop uses a feedback loop to store one bit

5.1 What an operating system is, and its main functions

• ·Define an operating system and briefly describe its evolution
• ·List the main functions of an OS: providing interfaces, process management, resource management, security
• ·Classify OS types: single/multi user, single/multi task, multi-threading, real-time, time-sharing

5.2 File and directory management

• ·Explain file types/extensions, file hierarchy and file systems (e.g. FAT)
• ·Describe file security (passwords, access privileges) and storage allocation methods: contiguous, linked, indexed
• ·Explain defragmentation and the need for disk formatting

5.3 Process management

• ·Distinguish a process from a program and list the process states
• ·Draw and explain the seven-state process transition diagram
• ·Compare long/short/medium-term schedulers and describe the process control block

5.4 Memory and I/O device management

• ·Explain the role of the Memory Management Unit and virtual memory (paging)
• ·Describe how the OS manages I/O devices through device drivers and spooling

6.1 Signals and their properties

• ·Represent digital and analog signals graphically
• ·Solve numeric problems relating amplitude, frequency, wavelength and phase

6.2 Signal transmission media

• ·Classify guided media (twisted pair, coaxial cable, fibre optics) vs unguided media
• ·Explain how latency, bandwidth, noise, attenuation and distortion affect transmission

6.3 Digital data encoding

• ·Represent digital data using two-voltage-level encoding and Manchester encoding
• ·Explain the need for synchronization and how a parity bit detects a bit error

6.4 PSTN and modems

• ·Describe a PSTN as an analog voice-carrying line
• ·Explain modulation and demodulation and draw a schematic of two computers connected via modems over a PSTN line

6.5 Network topologies

• ·Explain why all-to-all connections are impractical, and describe bus topology and its media-access problem
• ·Draw and compare star, ring, mesh and bus topologies, and explain the role of hubs and switches

6.6 Media Access Control (MAC) protocol

• ·Explain the need for MAC addresses and frames as the unit of transmission
• ·Describe the evolution of media-access protocols from ALOHA to Ethernet

6.7 Interconnecting networks to form the Internet

• ·Explain the role of a gateway and the need for globally unique addressing independent of MAC/LAN technology
• ·Calculate subnet masks and IP address ranges for a given block of addresses and network size
• ·Describe DHCP, private IP addresses, routing/packet switching and best-effort delivery

6.8 Transport protocols

• ·Explain why process-to-process (not just host-to-host) delivery is needed, and the role of port numbers/multiplexing
• ·Compare TCP and UDP properties and list applications that use each

6.9 Applications on the Internet: DNS and HTTP

• ·Explain why DNS translates human-friendly names to IP addresses, and describe its hierarchical structure
• ·Describe a simple HTTP GET request/response and the client-server model

6.10 TCP/IP and OSI reference models

• ·List and describe the layers of the TCP/IP and OSI models and the function of each
• ·State the data unit (packet/frame/bit) associated with each relevant layer

6.11 Security of communication and connected devices

• ·Explain public-key/private-key encryption and digital signatures at a basic level
• ·Describe threats (viruses, trojans, malware, phishing) and protections (firewalls, antivirus, awareness)

6.12 ISPs and connecting home networks

• ·Describe the role of an ISP and how modems/DSL/ADSL connect a home to it
• ·Explain the role of NAT/proxies in a home LAN that uses private IPs

7.1 Characteristics of systems

• ·Define a system and list its characteristics
• ·Classify systems as open/closed, natural/manmade, living/physical — with examples

7.2 Types of manmade information systems

• ·Compare OAS, TPS, MIS, DSS, ESS, GIS, KMS, CMS and ERPS by objective and functionality

7.3 System development lifecycle models and methodologies

• ·List and describe the waterfall, spiral, agile, prototyping and RAD models
• ·Compare structured vs object-oriented development methodologies

7.4 Structured System Analysis and Design Methodology (SSADM)

• ·Define SSADM and list the SDLC stages it covers

7.5 Preliminary investigation and feasibility study

• ·Describe the tasks of preliminary investigation and how information problems/priorities are identified
• ·Explain technical, economic, operational and organizational feasibility

7.6 Requirement analysis: DFDs, BAM and logical data modelling

• ·Distinguish functional from non-functional requirements and write requirements in IEEE-style form
• ·Draw a Business Activity Model, context diagram, document flow diagram and levelled Data Flow Diagrams (DFDs) for a given scenario
• ·Write Elementary Process Descriptions (EPDs) and draw a Logical Data Structure (LDS)
• ·Propose and justify a Business System Option (BSO)

7.7 Logical and physical design of the proposed system

• ·Produce logical DFDs and elementary process descriptions for the proposed (to-be) system
• ·Design a user interface and a logical data structure for the proposed system
• ·Specify table/record specifications and a data dictionary for the physical database design

7.8 Development and testing

• ·List the testing methods: white-box, black-box, unit, integration, system, acceptance testing
• ·Describe what each testing method checks and when it is used

7.9 Deployment of the developed system

• ·Compare parallel, direct, pilot and phased deployment/changeover methods
• ·Describe post-implementation activities: installation, data migration, training, review and maintenance

7.10 Implementation with off-the-shelf packaged systems

• ·Weigh the costs/benefits of off-the-shelf packages against custom development
• ·Describe business process gap analysis, mapping and reengineering

8.1 Database basics and database models

• ·Distinguish data from information, and structured from unstructured data
• ·Define a database and compare flat-file, hierarchical, network, relational and object-relational models

8.2 Components of the relational database model

• ·Define relations/tables, attributes/columns, tuples/rows and relationships
• ·Explain NOT NULL, unique, primary key, foreign key and check constraints

8.3 SQL: data definition and data manipulation

• ·Write DDL to create, alter and drop tables and databases, including adding/removing keys
• ·Write DML — INSERT, UPDATE, DELETE and SELECT — including single- and multi-table SELECTs using an inner join

8.4 ER diagrams (conceptual schema)

• ·Identify entities, attributes, entity identifiers and relationships from a worded scenario
• ·Draw an ER diagram with correct cardinality notation
• ·Explain the Extended ER (EER) concept at a basic level

8.5 Logical schema design

• ·Define logical schema and relation instances
• ·Distinguish candidate key, primary key, alternate key, foreign key and domain

8.6 Transforming ER diagrams to a logical schema

• ·Transform entities, attributes and relationships from an ER diagram into a relational logical schema

8.7 Normalization

• ·Identify insert, update and delete anomalies caused by redundancy
• ·Define full, partial and transitive functional dependency
• ·Normalize a given unnormalized table through 1NF, 2NF and 3NF, showing the working at each step

9.1 The problem-solving process

• ·Describe the steps of the problem-solving process: understand, define, plan, implement

9.2 Top-down design and stepwise refinement

• ·Apply stepwise refinement/modularization to break a problem into sub-problems
• ·Draw a structure chart for a given solution

9.3 Algorithms: flowcharts, pseudocode and hand tracing

• ·Draw a flowchart using standard symbols for a given problem
• ·Write pseudocode for a given problem
• ·Hand-trace an algorithm to verify its output for given input

9.4 Programming paradigms

• ·Compare imperative, declarative and object-oriented paradigms

9.5 Program translators

• ·Compare interpreters, compilers and the hybrid approach, and describe the role of a linker

9.6 Integrated development environments (IDE)

• ·Identify IDE features (open/save, compile/execute, debug) and use them practically

9.7 Program structure, data types, operators and I/O

• ·Identify a Python program's structure, comments, constants/variables and primitive data types
• ·Use arithmetic, relational, logical and bitwise operators with correct precedence
• ·Write code that reads keyboard input and prints output to standard devices

9.8 Control structures

• ·Use sequence, selection (if/elif/else) and repetition (for/while) structures correctly
• ·Apply nested control structures to solve a multi-step problem
• ·Predict the output of a given Python code segment containing control structures

9.9 Sub-programs and functions

• ·Distinguish built-in from user-defined functions and describe function structure
• ·Use parameters, arguments, return values and default values correctly
• ·Compare local vs global variable scope and lifetime

9.10 Data structures: strings, lists, tuples, dictionaries

• ·Use strings, lists, tuples and dictionaries appropriately in a Python program
• ·Choose the correct data structure for a described data-storage need

9.11 File handling

• ·Open, read, write, append and close files using basic file operations in Python

9.12 Managing data in databases from a program

• ·Embed SQL statements in a Python program to connect to, retrieve from, and modify a database

9.13 Searching and sorting

• ·Implement sequential search and trace it on a given list
• ·Implement bubble sort and trace it step-by-step on a given list

10.1 The need for the web and types of websites

• ·Describe the WWW and classify website types: informational, personal, educational, commercial, portal

10.2 Analysing user requirements for a website

• ·Plan a website's objectives, page content and navigation structure before building it

10.3 HTML basics: a single web page

• ·Use html/head/title/body structure tags correctly
• ·Apply text-formatting tags: headings, paragraph, line break, bold/italic/underline, font size/colour

10.4 HTML: linked pages, lists, tables and multimedia

• ·Create hyperlinks — bookmark, local link, external link — between pages and sections
• ·Build ordered/unordered/definition lists and tables, including merged cells, with correct tags
• ·Embed images, audio and video in a page

10.5 CSS: styling web pages

• ·Write CSS using element, id, class and group selectors with correct syntax
• ·Apply internal, external and inline CSS to format backgrounds, text, links, lists and tables

10.6 Using a web authoring tool

• ·Use a web authoring tool practically to build web pages

10.7 Dynamic web pages with PHP and MySQL

• ·Embed PHP — variables, arrays, control structures, functions — into a web page
• ·Connect PHP to MySQL to save and retrieve form data
• ·Build an HTML form (text/password inputs, radio, checkbox, select, submit) that posts to a PHP script

10.8 Publishing and maintaining websites

• ·Publish a website locally and to a free web-hosting service
• ·Identify factors affecting website performance

11.1 Microprocessor development systems

• ·Identify Arduino/Raspberry-Pi-style boards and their features: analog/digital I/O, microprocessor, RX/TX pins, USB port, power supply, reset switch
• ·Describe simple applications: switching an LED, light/temperature sensing, magnetic door-switch detection

11.2 Internet of Things concepts and a simple application

• ·Define IoT, its needs and its enabling technologies
• ·Design a simple remote-switch IoT application, e.g. turning a device on/off over the Internet

12.1 ICT's role in business

• ·Define digital economy and new digital business methods: reverse auctions, group purchasing, e-marketplace
• ·Distinguish pure-brick, brick-and-click and pure-click organizations
• ·Describe how ICT supports accounting, HR, production, marketing, supply chain and communication functions

12.2 E-commerce and e-business

• ·Distinguish e-commerce from e-business
• ·List and exemplify B2B, B2C, C2C, C2B, B2E and G2C transaction types
• ·State advantages and disadvantages of e-business

12.3 E-marketing

• ·Define e-marketing and describe ICT's role in it (web advertising, mobile marketing)
• ·Explain how databases support predicting customer behaviour and gaining competitive advantage

13.1 Intelligent and emotional computing

• ·Describe intelligent and emotional computing, and explain artificial intelligence at a basic level
• ·Discuss man-machine and machine-to-machine coexistence

13.2 Agent technology

• ·Describe software agents and multi-agent systems and their characteristics
• ·Identify real-world applications of agent systems

13.3 Beyond the von-Neumann model

• ·Describe nature-inspired and biology-inspired computing directions
• ·Explain the fundamentals of quantum computing at an introductory level

14.1 Designing the information system

• ·Apply the full SAD methodology from Unit 7 — investigation, analysis, design — to a real, self-chosen information system
• ·Maintain an activity logbook recording each session's work for teacher verification

14.2 Implementing and demonstrating the system

• ·Build and demonstrate a working information system implementing the designed solution
• ·Present and defend the design decisions to the teacher/assessor