Maintainability

Maintainable code is code that can be read, understood, and fixed by other developers. There are a few best-practice techniques to help write maintainable code, including:

Comments

Comments should be used throughout the code to:
- Explain complex processes.
- Clarify the purpose of algorithms.
- Clarify the purpose of a subroutine, as well as its parameters and return type and value.

Indentation

It is good practice to keep indentation of code consistent throughout the code.
When a new block of code opens, it should be indented to the right.
When a block of code closes, it should return to the left.
This makes code easier to read by visualising the scopes involved.

Identifier names

Identifier names should be clear about their purpose. For example, which of the following two examples makes more sense:
- newBalance = oldBalance * INTEREST_RATE;
- a = b * c;

Code structure

Code should be well structured through the use of subroutines.
This allows people to identify a single subroutine that they need to reuse or work on.

Parameters vs global variables

It is good practice to pass data around the program using parameter passing rather than using global variables.
This is because passing parameters prevents other subroutines from unexpectedly changing the value of the variables.

1Problem Solving

1.1Algorithms

1.1.1Algorithm Thinking

1.1.2Interpreting Algorithms

1.1.3Expressing Algorithms - Pseudocode

1.1.4Expressing Algorithms - Flow Charts

1.1.5Correcting Algorithms

1.1.6Completing Algorithms

1.1.7Search Algorithms

1.1.8Linear Search

1.1.9Binary Search

1.1.10Sort Algorithms

1.1.11Bubble Sort

1.1.12Merge Sort

1.2Decomposition & Abstraction

1.2.1Computational Thinking - Abstraction

1.2.2Computational Thinking - Decomposition

1.2.3End of Topic Test - Algorithms

2Programming

3Data

3.1Binary

3.1.1Number Bases

3.1.2Negative Binary Numbers

3.1.3Binary Addition

3.1.4Binary Shifts

3.2Data Representation

3.2.1Representing Text

3.2.2ASCII

3.2.3Unicode

3.2.4Representing Images

3.2.5Representing Sound

3.3Data Storage & Compression

3.3.1Capacity

3.3.2Calculating Capacity Requirements

3.3.3Data Compression

3.3.4Run Length Encoding

3.4Encryption

3.4.1Encryption

3.4.2Caesar Cipher

3.4.3Ciphers

3.5Databases

3.5.1Databases

3.5.2End of Topic Test - Data & Representation

4Computers

4.1Machines & Computational Modelling

4.1.1Computational Models

4.1.2Input-Process-Output Model

4.2Hardware

4.3Logic

4.3.1Binary Systems

4.3.2Logic Circuits

4.3.3Boolean Logic

4.3.4End of Topic Test - Logic

4.4Software

4.4.1Operating Systems

4.4.2User Interface Managetment

4.4.3Memory and Process Management

4.4.4File Management

4.4.5Device Management

4.4.6User Management

4.4.7Encryption Software

4.4.8Defragmentation Software

4.4.9Data Compression Software

4.4.10Backup Software

4.5Programming Languages

4.5.1High Level Languages

4.5.2Low Level Languages

4.5.3Translators - Compilers

4.5.4Translators - Interpreters

4.5.5Translators - Assemblers

4.5.6End of Topic Test - Translation & Representation

5Communication & The Internet

5.1Networks

5.2Network Security

5.2.1User Access Levels

5.2.2Encryption

5.2.3Protecting Against Malware

5.2.4Firewalls

5.2.5Forms of Attack

5.2.6Penetration Testing

5.2.7Malware

5.2.8How Malware Spreads

5.2.9Social Engineering

5.2.10Protecting Against Social Engineering

5.2.11Phishing

5.2.12Network Administration

5.2.13Network Forensics

5.3The Internet & the World Wide Web

5.3.1IP Addresses

5.3.2Types of IP Address

5.3.3MAC Addresses

5.3.4Packet Switching

5.3.5How Do Packets Get Routed?

5.3.6Did My Data Arrive Safely?

5.3.7The Internet

5.3.8URLs

5.3.9DNS

5.3.10Web Hosting

5.3.11End of Topic Test - Security

6The Bigger Picture

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