https://smartrevise.craigndave.org/
1.1 Data representation
1.1.1 Binary systems ✓
1.1.2 Hexadecimal ✓
1.1.3 Data storage ✓
1.2 Communication and Internet technologies
1.2.1 Data transmission ✓
1.2.2 Security aspects ✓
1.2.3 Internet principles of operation ✓
1.3 Hardware and software
1.3.1 Logic gates ✓
1.3.2 Computer architecture and the fetch-execute cycle ✓
1.3.3 Input devices
1.3.4 Output devices
1.3.5 Memory, storage devices and media
1.3.6 Operating systems
1.3.7 High- and low-level languages and their translators
1.4 Security
1.5 Ethics
https://revise.znotes.org/cie-igcse/computerscience-0478