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## AQA (8520) GCSE Computer Science

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### GCSE AQA 8520 Computer Science

3.1

Fundamentals of algorithms

3.1.1

Representing algorithms

Computational thinking

• Decomposition
• Pattern recognition
• Abstraction
• Algorithms

Flowcharts

• Standard Shapes
• Algorithms

Pseudocode

• Syllabus pseudocode

3.1.2 - 3.1.4

Types of algorithms

Algorithm efficiency

• Time efficiency
• Space efficiency

Searching algorithms

• Linear search
• Binary Search

Sorting algorithms

• Bubble Sort
• Merge Sort

3.2

Programming

3.2.1 - 3.2.6

Programming components

Data types

• Character
• String
• Integer
• Real
• Boolean

Variables and constants

• Naming
• Assigning
• Uses

Operators

• Arithmetic
• Boolean
• Relational

Sequence, selection, iteration

• IF
• WHILE
• CASE
• REPEAT
• FOR
• Nesting

Data Structures

• List
• Dictionary
• Tuple

Arrays & Records

• 1D Array
• 2D Array
• Array operations
• Records

3.2.7 - 3.2.10

Processes

File handling

• Open
• Close
• Write

String handling

• Storage
• Search
• Properties
• Type casting
• Character codes

Random number generation

• Random integers
• Python examples
• Uses

Subroutines

• Coding
• Functions
• Scope
• Uses

3.2.11 - 3.2.13

Writing programs

Structured programming

• Planning
• Iteration
• Subroutines\Functions
• Modules & Scope
• Python Examples

Validation and authentication

• Length check
• Range check
• Authentication
• Test Data
• Python Examples

Programming languages

• Machine code
• Low Level
• High level
• Translators, Assemblers
• Compiler, Interpreters

3.3

Fundamentals of data representation

3.3.1 - 3.3.4

Representing numbers

Denary and Binary

• Number systems
• Denary to Binary
• Binary to Denary
• Binary Shift

• Uses
• Denary to Hex
• Hex to Denary
• Hex to Binary
• Binary to Hex

Units and prefixes

• Bit, Byte, Nibble
• Kilobyte to Petabyte

3.3.5 - 3.3.7

Creating files

Character sets

• ASCII
• Extended ASCII
• Character Sets
• Unicode

Images

• Pixels
• Grayscale
• Colour Depth
• Files size

Sound

• Sampling
• Sampling frequency
• Bit Depth, Bit Rate
• Channels

3.3.8

Compression

• Lossy compression
• Lossless compression
• Dictionary compression
• Images,Video,Music

Huffman Encoding

• Binary Tree
• Creating keywords
• Encoding

Run Length Encoding

• RLE data format
• RLE & Images
• RLE & Text

3.4

Computer Systems

3.4.1 Hardware and Software

Hardware, software

• Computer System
• Hardware
• Software

3.4.2 Boolean Logic

Boolean logic

• AND, OR, NOT
• Logic Circuits
• Truth Tables

3.4.3 Software Classification

Software types

• System Software
• Application Software

Operating systems

• Purpose
• Kernel
• User Interface
• Device Drivers

3.4.4

Systems Architecture: CPU

CPU and Von Neumann architecture

• What is it
• ALU, Control Unit
• Clock, Buses
• Von Neumann

CPU performance

• Cache
• Cores
• Overclocking
• Parallel processing

Fetch-Execute cycle

• Hardware used
• The FDE cycle

3.4.4

Systems Architecture: Memory

Types of memory

• RAM Random Access
• DRAM and SRAM

Secondary storage

• Magnetic
• Optical
• Solid State
• Cloud

Embedded systems

• Definition
• Sensors
• Analog-Digital converter
• Actuators

3.5

Networks

Networks

PANs, LANs and WANs

• PAN
• LAN at home
• WAN

Networks type and shape

• Wired, Wireless networks
• Star, Bus topology
• Star & Bus animations
• Network Builder

Network protocols

• TCP/IP and UDP
• HTTP and HTTPs
• FTP, Ethernet, Wi-Fi
• Email Protocols

Network security

• Importance of security
• Authentication methods
• Encryption
• Firewalls
• MAC filtering

Four Layer Model

• Application Layer
• Transport Layer
• Network Layer

3.6

Cyber security

3.6.1

Cyber security threats

Introduction to Cyber-security

• What is it
• Why is it important
• Malicious code
• Social engineering
• Prevention

Penetration testing

• What is it
• White box testing
• Black box testing

Social engineering

• What is it
• Phishing
• Pharming
• Blagging
• Other Social attacks

Malware

• Viruses and Worms
• Browser malware
• Other malware types

3.6.2

Prevention

Threats and Prevention

• Typical threats
• Biometric authentication
• Email confirmation

3.7

Societal Impact

3.7.1

Ethical, Legal, Environmental

Ethical

• Internet
• Social media
• Digital divide
• Whistleblowing
• Self driving cars
• Genetic screening
• Drone use

Cultural

• Anonymity
• Citizen Journalism
• Military Drones
• Health & Technology
• Social Network Impacts

Legislation

• Data Protection Act
• Computer Misuse Act
• Freedom of Information Act

Environmental

• E-Waste
• Sustainability
• Recycling
• Energy use
• Data Centres
• Monitoring
• Stakeholders

Open-Close Source

• Open Source
• Closed Source
• Creative Commons

Privacy

• DNA profiling
• ID Cards
• CCTV
• Tracking
• Personal Data
• Stakeholders