O Level Computer Science (2210) Notes

Every chapter of the computer science syllabus for Cambridge O Level 2210, in the order the book takes them. 25 chapters have a finished lesson — notes, worked examples, a graph you can move, flashcards and a quiz. The rest are mapped and being written.

Also called Cambridge O Level, CAIE O Level.

01

Data representation

▸Number SystemsWhy a machine that only knows two symbols can represent anything · 20 min · 8 questions→▸Text, Sound and ImagesHow a machine that stores only numbers holds a photograph · 20 min · 8 questions→▸Data Storage and CompressionMaking files smaller, and deciding what you can afford to lose · 18 min · 8 questions→

02

Data transmission

▸Types and Methods of Data TransmissionPackets, wires and directions — how data actually gets from one machine to another · 18 min · 8 questions→▸Methods of Error DetectionNoticing that data arrived wrong, and sometimes fixing it · 18 min · 8 questions→▸EncryptionMaking intercepted data useless, and why the method being public does not matter · 18 min · 8 questions→

03

Hardware

▸Introduction to SystemsWhat is actually inside the box, and how it runs a program · 20 min · 8 questions→▸Input and Output DevicesGetting data in and results out, and choosing the right device for the job · 18 min · 8 questions→▸Data Storage and Virtual MemoryThree technologies, and the trick that lets a machine run more than it can hold · 18 min · 8 questions→▸Computer NetworksHow a message crosses the world in fragments and arrives whole · 22 min · 6 questions→

04

Software

▸Software SystemThe layers between a program and the hardware it runs on · 18 min · 8 questions→

05

The internet and its uses

▸The Internet and the World Wide WebTwo different things, and what actually happens when you type an address · 18 min · 8 questions→▸Emerging Technologies in Computer ScienceWhat the newer technologies actually do, and what each is bad at · 18 min · 8 questions→▸Cyber SecurityThe threats named in the syllabus, and the specific defence against each · 20 min · 8 questions→

06

Automated and emerging technologies

▸Automated Systems and RoboticsSensor, processor, actuator — and the comparison that makes it control rather than monitoring · 18 min · 8 questions→▸Introduction to Artificial Intelligence and Machine LearningWhat it means for a program to learn from data instead of being told the rules · 20 min · 8 questions→

07

Algorithm design and problem-solving

▸Computational ThinkingBreaking a problem down until every piece is something you can actually do · 20 min · 8 questions→▸Algorithms & Big-OSorting, searching, and measuring cost honestly · 22 min · 6 questions→

08

Programming

▸Introduction to Python ProgrammingVariables, types, input and output — the whole vocabulary of a first program · 20 min · 8 questions→▸Control Structures in PythonChoosing, repeating, and knowing which loop the problem needs · 20 min · 8 questions→▸Data StructuresArrays, lists, stacks, queues, trees · 24 min · 6 questions→▸File Handling in CMaking data outlive the program that created it · 18 min · 8 questions→

09

Databases

▸Basic Concepts and Terminologies of DatabasesKeys, relationships and the software that holds it all together · 20 min · 8 questions→▸Table and QueryAsking the database a question, and getting only the rows you wanted · 20 min · 8 questions→

10

Boolean logic

▸Digital Systems and Logic DesignGates, truth tables, and building arithmetic out of switches · 20 min · 8 questions→