Cambridge International · 9618
CS AS Level
Complete Notes
Everything you need for your Cambridge AS Level Computer Science exams — clear, detailed, and exam-ready.
PAPER 1
Theory Fundamentals — Sections 1 to 8
PAPER 2
Problem-solving & Programming — Sections 9 to 12
Paper 1 — Theory Fundamentals 75 marks · 1h 30min
Covers Chapters 1–8. Tests knowledge (AO1) and application (AO2). Written paper — no coding required.
Chapter 1
Information Representation
Binary, hex, BCD, two's complement, character sets, bitmap images, vector graphics, sound encoding and compression techniques.
1.1 Data Representation
1.2 Multimedia
1.3 Compression
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Chapter 2
Communication
LAN, WAN, network topologies, client-server, cloud computing, IP addressing, DNS, Ethernet and bit streaming.
2.1 Networks & Internet
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Chapter 3
Hardware
Computer components, memory types (RAM/ROM/SRAM/DRAM), storage devices, embedded systems, logic gates and circuits.
3.1 Components
3.2 Logic Gates
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Chapter 4
Processor Fundamentals
Von Neumann model, CPU registers, the Fetch-Execute cycle, assembly language, addressing modes, bit manipulation and interrupts.
4.1 CPU Architecture
4.2 Assembly
4.3 Bit Ops
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Chapter 5
System Software
Operating system functions, utility software, program libraries, assemblers, compilers, interpreters and IDE features.
5.1 Operating Systems
5.2 Translators
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Chapter 6
Security, Privacy & Data Integrity
Cyber threats, firewalls, encryption, validation vs verification, parity checks, checksums and data protection methods.
6.1 Data Security
6.2 Data Integrity
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Chapter 7
Ethics and Ownership
Professional ethics, BCS/IEEE, copyright law, software licensing (open source, shareware, commercial), and AI's societal impact.
7.1 Ethics & Ownership
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Chapter 8
Databases
Relational databases, ER diagrams, normalisation (1NF–3NF), DBMS features, SQL DDL and DML queries.
8.1 DB Concepts
8.2 DBMS
8.3 SQL
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Paper 2 — Problem-solving & Programming 75 marks · 2 hours
Covers Chapters 9–12. Tests design and programming skills (AO2 + AO3). Answers written in pseudocode — no actual code required.
Chapter 9
Algorithm Design & Problem-Solving
Computational thinking, abstraction, decomposition, flowcharts, pseudocode, structured English and stepwise refinement.
9.1 Comp. Thinking
9.2 Algorithms
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Chapter 10
Data Types and Structures
Data types, records, 1D/2D arrays, bubble sort, linear search, file handling and introduction to ADTs (stack, queue, linked list).
10.1 Data Types
10.2 Arrays
10.3 Files
10.4 ADTs
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Chapter 11
Programming
Variables, constants, operators, IF/CASE constructs, all loop types, procedures, functions and structured programming techniques.
11.1 Basics
11.2 Constructs
11.3 Structured Prog.
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Chapter 12
Software Development
Development life cycles (waterfall, iterative, RAD), structure charts, state-transition diagrams, testing methods and maintenance types.
12.1 Life Cycle
12.2 Design
12.3 Testing
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