Cambridge International A Level Computer Science
Paper 3 goes deep: floating point, protocols, RISC/CISC, virtual machines, encryption and AI. Paper 4 is the on-computer practical exam — data structures, OOP, recursion, file handling and exception handling.
Sitting AS and A2 together, all four papers in one series? Full A Level treats both halves as one course and pairs each A2 topic with the AS topic it builds on.
A2 Level Computer Science 9618
Course tourFollow the study route
21 sections in syllabus order. Each one: read, watch, pass a 5-question check, flashcards, real past-paper questions. A short check first tells you where to begin.
Paper 3
Advanced Theory
1h 30m75 marks25% of A Level
Written paper. Short-answer and structured questions.
Assessment objectives:AO1 60% Knowledge & understandingAO2 40% Apply & analysewhat each topic is examined as →
Data Representation
User-defined data types, file organisation and access, floating-point representation, normalisation and rounding errors.
Communication and Internet Technologies
Protocols (TCP/IP stack, HTTP, FTP, SMTP, POP3, IMAP, BitTorrent), circuit and packet switching in depth.
Hardware and Virtual Machines
RISC vs CISC, pipelining, parallel processing (SISD/SIMD/MISD/MIMD), massively parallel computers, virtual machines — plus Boolean algebra, De Morgan's laws, Karnaugh maps, adders and flip-flops.
System Software
Operating system internals — process management, scheduling algorithms, memory management (paging, segmentation, virtual memory) — and how compilers work (lexical, syntax, code generation, optimisation, RPN).
Security
Asymmetric encryption, digital signatures and certificates, SSL/TLS, quantum cryptography.
Artificial Intelligence
Graphs and graph algorithms (Dijkstra, A*), machine learning categories (supervised, unsupervised, reinforcement), deep learning, back-propagation and regression.
Paper 4
Practical
2h 30m75 marks25% of A Level
Practical exam on a computer using Python, VB.NET or Java. Evidence document submitted.
Assessment objectives:AO3 100% Design, program & evaluatewhat each topic is examined as →
Computational Thinking and Problem-Solving
Recursion, ADTs in code (stack, queue, linked list, binary tree, dictionary, hash table), searching and sorting (binary search, insertion sort, bubble sort), and Big O.
Further Programming
Programming paradigms (low-level, imperative, OOP, declarative), full object-oriented programming (classes, inheritance, polymorphism, encapsulation), file processing with random-access files, and exception handling.
