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## SQA National 4 & 5 Computing Science

The material on this site is not endorsed by the SQA examination board. We do not guarantee that it covers all of the relevant theory that is required for the examination. Please refer to the official syllabus to ensure that you are covering the material to the standard required.

Topics specific to Year 2 National level 5 are marked in the section menus with (N5)

### SQA National 4&5 Computing Science

1.1

Data and Computational Constructs

Data types

• What is a variable?
• Character
• String
• Integer
• Graphical
• Real (N5)
• Boolean (N5)
• Arrays (N5)

Operators

• Arithmetic
• Assignment
• Boolean
• Relational
• Concatenation

Constructs

• Sequence
• Selection
• Conditionals
• Iteration

Procedures

• Procedures
• Functions
• Round
• Random
• Casting (eg. INT)

1.2

Algorithms

Structure diagrams

• Decomposition
• Standard formats

Flowcharts

• Standard shapes
• Use in algorithms

Pseudocode

• What is pseudocode?
• Example algorithms

1.3

Testing

Validation and Test Data

• Length validation
• Range validation
• Test data

Errors

• Syntax
• Logic
• Execution

Maintainability

• Commentary
• Identifiers
• Whitespace
• Indentation

1.4

Low-level Operations

Units

• Bits
• Bytes
• Kb,Mb,Tb.Pb

Binary

• Use of binary
• Binary to denary (N5)
• Denary to binary (N5)
• Machine code
• High-level languages
• Interpreters
• Compilers

Real numbers (N5)

• Real numbers
• Mantissa Exponent
• Denary Floating
• Binary Floating

Representing characters

• Standard ASCII
• Extended ASCII (N5)
• Unicode (N5)

Bitmap images (N5)

• Pixels
• Colour depth
• File size

Vector images (N5)

• Vector images
• Formats
• Objects
• Bitmap vs. Vector

Computer architecture

• Architecture
• CPU
• ALU
• Control unit
• Computer memory
• Buses
• Interfaces

1.5

Contemporary Developments

Trends in programming languages and development environments

• First generation
• Second generation
• Third generation
• Fourth generation
• Fifth generation
• IDEs

2.1

Databases

Database structure

• Fields
• Field types
• Records
• Files
• Flat-file
• Relational

Keys

• Primary keys
• Compound keys
• Secondary keys
• Foreign keys
• Referential integrity

Validation

• Presence check
• Restricted choice
• Field length
• Range
• Check Digit

Database operation

• Searching
• Sorting
• Insert
• Delete
• Update
• Complex search

2.2

Web-based Structures

Structures

• Website
• Page
• URL

• Relative
• Absolute

• Need for navigation
• Examples

Web software

• Browsers
• Search engines

2.3

Media

File and media quality

• Resolution
• Colour depth
• Sampling rate
• File size (including units)
• Compression
• File formats

2.4

Designing Information Systems

Features

• Purpose
• Features
• Types of users
• Age of users

User interface

• Visuals
• Selection
• Consistency
• Interactivity

Coding (HTML)

Coding (Javascript)

Testing

• User interface
• Media display

2.5

Requirements of Information Systems

Hardware requirements

• Input/output devices
• Performance factors
• Processors
• Memory

Software requirements

• Types of software
• Application software
• Operating systems

Operating systems

• Purpose
• Kernel
• User Interface (HCI)
• Device Drivers

Web browsers

• OS support
• Privacy modes
• Accessibility

Storage devices

• Magnetic
• Optical
• Solid state
• Storage interfaces
• Firewire
• USB

Choosing storage

• Local vs Remote
• Capacity
• Portability
• Other concerns

2.6

Networks

Types of network

• Client/Server
• Peer-to-Peer
• Wired
• Wireless
• Optical

Network hardware

• NIC
• Hub
• Switch
• Router
• Ethernet
• Wireless hardware

2.7

Security

Malware and Hacking

• Viruses
• Worms
• Trojans
• Browser malware
• Keyloggers
• DOS/DDOS

Social Hacking

• Phishing
• Pharming
• Fraud
• Identity theft

Prevention

• Anti-virus
• Biometrics
• Firewalls

2.8

Information Systems and Society

Legislation

• Data Protection Act
• Computer Misuse Act
• Copyright, Designs & Patents Act
• Communication Acts
• Health and Safety

Environment

• E-waste
• Recycling
• Energy use
• Carbon footprints