Fundamentals of algorithms
Decomposition & abstraction, pseudo-code & flowcharts, trace tables, efficiency, and the searching and sorting algorithms.
Representing Algorithms
Decomposition, abstraction, AQA pseudo-code and flowcharts.
CS-L1-02Trace Tables
Follow an algorithm step by step and record every variable.
CS-L1-03Efficiency of Algorithms
Counting steps — why one algorithm beats another.
CS-L1-04Searching — Linear & Binary
Two ways to find a value in a list.
CS-L1-05Sorting — Bubble & Merge
Two classic ways to put a list in order.
ReviewCS-L1-06Unit 1 Review & Exam Prep
Recap every spec point and practise exam questions.
Programming
Data types, the three constructs, operators, arrays & records, strings, subroutines, and robust & secure programming.
Data Types
Integer, real, Boolean, character, string — and casting.
CS-L2-02Variables & Constants
Named stores that change, and values that don't.
Selection
IF / ELSE IF / ELSE and nested decisions.
CS-L2-04Iteration — Loops
Count- and condition-controlled loops (FOR, WHILE, REPEAT).
Arithmetic Operations
+ − * / and integer division DIV & MOD.
CS-L2-06Relational & Boolean Operations
Comparisons and AND / OR / NOT.
Arrays — 1-D & 2-D
Indexed collections of items of the same type.
CS-L2-08Records
Group related fields of different types.
Input, Output & Random Numbers
USERINPUT, OUTPUT and RANDOM_INT.
CS-L2-10String Handling
Length, substring, position, concatenation, case, char codes.
Subroutines — Procedures & Functions
Reusable named blocks, parameters and return values.
CS-L2-12Scope & Structured Programming
Local vs global variables; modular design.
Validation & Authentication
Check input is sensible; confirm identity.
CS-L2-14Testing & Test Data
Normal, boundary and erroneous data; error types.
ReviewCS-L2-15Unit 2 Review & Exam Prep
Recap every spec point and practise exam questions.
Fundamentals of data representation
Number bases, units of information, binary arithmetic, character/image/sound encoding and data compression.
Number Bases
Denary, binary and hexadecimal — and why each is used.
CS-L3-02Binary ↔ Denary Conversion
The place-value method, both directions.
CS-L3-03Hexadecimal & Conversions
Nibbles, and binary / denary ↔ hex.
Units of Information
Bit, nibble, byte, kB, MB, GB, TB.
CS-L3-05Binary Addition
Adding bytes — carrying and overflow.
CS-L3-06Binary Shifts
Logical shifts that multiply and divide by 2.
Character Encoding
ASCII and Unicode character codes.
CS-L3-08Representing Images
Pixels, resolution, colour depth, file size.
CS-L3-09Representing Sound
Sampling, sample rate, bit depth, file size.
Data Compression
Lossy vs lossless; RLE and Huffman coding.
ReviewCS-L3-11Unit 3 Review & Exam Prep
Recap every spec point and practise exam questions.
Computer systems
Hardware & software, Boolean logic, software classification, translators, and systems architecture (CPU, memory and storage).
Hardware & Software
The physical parts and the programs — and how they depend on each other.
CS-L4-02Boolean Logic — Gates & Truth Tables
AND, OR and NOT gates, their symbols and truth tables.
CS-L4-03Logic Circuits
Combine gates; work out a circuit's output and expression.
Software Classification
System vs application; the OS and utility software.
CS-L4-05Programming Languages & Translators
Low/high level; assembler, compiler, interpreter.
The CPU & Von Neumann Architecture
ALU, control unit, registers and cache.
CS-L4-07Fetch–Decode–Execute Cycle
How the CPU runs instructions; the key registers.
CS-L4-08CPU Performance
Clock speed, cores and cache.
Memory & Storage
RAM vs ROM; magnetic, optical and solid-state storage.
ReviewCS-L4-10Unit 4 Review & Exam Prep
Recap every spec point and practise exam questions.
Fundamentals of computer networks
Network types & topologies, hardware, the internet & DNS, protocols, the TCP/IP layers, packet switching and encryption.
Networks & Network Types
What a network is; advantages/disadvantages; PAN, LAN and WAN.
CS-L5-02Wired & Wireless Networks
Cables vs radio waves; factors affecting network performance.
CS-L5-03Network Topologies
The star and bus layouts — and their trade-offs.
Network Hardware
NIC, switch, router, WAP and transmission media.
CS-L5-05The Internet, DNS & the Cloud
How the internet finds things; hosting and the cloud.
Network Protocols
TCP, IP, HTTP, HTTPS, FTP, SMTP and IMAP.
CS-L5-07The TCP/IP 4-Layer Model
Application, transport, internet and link layers.
CS-L5-08Packet Switching
Packets, headers, and routing data across the internet.
Encryption & Network Security
Plaintext, ciphertext, keys, and securing data in transit.
ReviewCS-L5-10Unit 5 Review & Exam Prep
Recap every spec point and practise exam questions.
Cyber security
Threats — social engineering, malware, brute force, DoS, interception and SQL injection — plus how to detect and prevent them.
Cyber Security & Threats
What cyber security is and the main threat types.
CS-L6-02Social Engineering
Blagging, phishing, pharming and shouldering.
CS-L6-03Malware
Virus, worm, trojan, ransomware and spyware.
Brute-Force & Password Attacks
Guessing passwords; weak and default password risks.
CS-L6-05Denial of Service & Data Interception
Flooding a service offline; sniffing data in transit.
CS-L6-06SQL Injection
Attacking a database through an input box.
Penetration Testing
Authorised attacks to find weaknesses first; white vs black box.
CS-L6-08Identifying & Authenticating Users
Passwords, biometrics, CAPTCHA, email confirmation and 2FA.
CS-L6-09Protecting Systems
Anti-malware, firewalls, access levels, encryption, updates, physical security.
Unit 6 Review & Exam Prep
Recap every spec point and practise exam questions.
Relational databases & SQL
Databases vs flat files, tables/records/fields, primary & foreign keys, and SQL — SELECT, WHERE, LIKE, ORDER BY and INSERT.
Databases & Flat Files
What a database is; redundancy and inconsistency.
CS-L7-02Relational Databases
Tables, records and fields.
CS-L7-03Primary & Foreign Keys
Uniquely identifying records and linking tables.
SQL: SELECT & FROM
Retrieving chosen columns, or all with *.
CS-L7-05SQL: WHERE & Logical Operators
Filtering rows; AND, OR and comparisons.
CS-L7-06SQL: Wildcards with LIKE
Pattern matching with % and _.
CS-L7-07SQL: ORDER BY
Sorting results ascending and descending.
SQL: INSERT INTO
Adding a new record with matching values.
CS-L7-09Building Complete Queries
Combine SELECT, WHERE, LIKE and ORDER BY.
Unit 7 Review & Exam Prep
Recap every spec point and practise exam questions.
Ethical, legal & environmental impacts
Privacy, ethical & cultural issues, the three UK Acts, software licensing, environmental impacts and extended-response technique.
Impacts of Technology — The Big Picture
The five impact lenses and stakeholders.
CS-L8-02Privacy & Personal Data
How data is collected; benefits vs privacy risks.
CS-L8-03Ethical & Cultural Issues
Digital divide, misinformation, bias and censorship.
The Data Protection Act 2018
Controlling personal data; the key principles.
CS-L8-05The Computer Misuse Act 1990
Hacking and malware as criminal offences.
CS-L8-06Copyright, Designs & Patents Act 1988
Protecting creative work; infringement.
CS-L8-07Software Licensing
Open source versus proprietary software.
Environmental Impacts
E-waste, energy use and responsible computing.
CS-L8-09Emerging Technology & Extended Responses
AI, autonomous vehicles, wearables; how to answer 'Discuss'.
Unit 8 Review & Exam Prep
Recap every spec point and practise exam questions.