Rapid Review
All of computer science,
refreshed in one sitting.
Eleven subjects covering the undergraduate syllabus, written to be read straight through in about 7.9 hours. Deep enough that you can re-derive an answer, short enough to finish the night before.
- subjects
- 11
- hours end to end
- 7.9
- chapters
- 85
- self-check questions
- 118
Read this if
You studied this material once and need it back — before a viva, an oral exam, a screening round, or a job you have not interviewed for in a while.
Not this if
You are meeting a subject for the first time. This is revision, not instruction — it moves at the pace of someone reminding you, not teaching you.
Foundations
3 subjects · 2 hr 13 minThe layer everything else assumes you already have: how programs are structured, how data is organised, and the mathematics used to reason about both.
- 45 min
Programming Fundamentals & OOP
How programs are structured before any of the rest matters: memory, scope, parameter passing, the four pillars, and the design principles examiners actually ask you to name.
11 chapters · 10 questions - 60 min
Data Structures & Algorithms
Every structure and algorithm a syllabus expects, with the complexities that get asked and the conditions under which the textbook answer is wrong.
11 chapters · 12 questions - 28 min
Discrete Mathematics
The reasoning toolkit the rest of computer science quietly assumes: logic, proof, sets and relations, counting, recurrences and the number theory behind cryptography.
8 chapters · 10 questions
Systems
3 subjects · 2 hr 40 minWhat sits between your source code and the electrons - the operating system that schedules it, the network that carries it, and the hardware that runs it.
- 60 min
Operating Systems
The most-examined subject on any CS syllabus. Processes and threads, scheduling, synchronisation, deadlock, virtual memory, page replacement, file systems and disk scheduling.
10 chapters · 12 questions - 55 min
Computer Networks
From the wire to the browser: the layered models, subnetting arithmetic, TCP's reliability machinery, routing, DNS and HTTPS — with the numbers examiners ask you to compute.
7 chapters · 12 questions - 45 min
Computer Architecture & Organization
How a machine actually executes an instruction: number representation, the datapath, pipelining and its hazards, the cache hierarchy, and the arithmetic of measuring performance.
7 chapters · 10 questions
Data & Theory
3 subjects · 2 hr 8 minStoring data correctly under concurrency, the formal limits of what machines can compute, and how source text becomes an executable.
- 60 min
Database Management Systems
ER modelling through to recovery: keys, relational algebra, the SQL that gets asked, normalisation up to BCNF, indexing, ACID, concurrency control and the NoSQL contrast.
9 chapters · 12 questions - 40 min
Theory of Computation
The formal limits of machines: automata and the languages they recognise, the Chomsky hierarchy, undecidability, and what P versus NP actually claims.
6 chapters · 10 questions - 28 min
Compiler Design
The pipeline that turns source text into an executable, phase by phase — and what each phase can and cannot catch.
6 chapters · 10 questions
Engineering Practice
2 subjects · 55 minHow software is actually built and shipped by teams, and how it is kept from being trivially broken into.
- 30 min
Software Engineering
How software is planned, structured, tested and shipped by teams: process models, requirements, coupling and cohesion, UML, the testing pyramid, and CI/CD.
5 chapters · 10 questions - 25 min
Security & Cryptography
The security vocabulary every CS graduate is expected to have: the CIA triad, symmetric and asymmetric cryptography, hashing, digital signatures, TLS, and the attack classes that keep recurring.
5 chapters · 10 questions