GCSE Computer Science OCR J277 - Topics to revise

Sep 5, 2026

Revision guide for GCSE Computer Science OCR J277, focused on preparing for mock exams. Covers core topics across system architecture, memory and storage, systems software, networks, and system security. Explains key concepts such as CPU components and the fetch–execute cycle, clock speed and multi-core performance, RAM/ROM/flash and secondary storage choices, operating system functions and utility software, network types, topologies, performance factors, DNS and hosting, packet switching and protocols, plus common security threats including malware and attack categories.

LanguageEnglish

CategoryExam

FormatPDF

Pages4

Reading Time10 min

AccessFree to download

Topics to revise

System Architecture

Memory and Storage

Systems Software

Networks

System Security

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FAQs

Which topics does the revision guide cover for OCR J277?

It covers system architecture, memory and storage, systems software, networks, and system security.

What are the main ideas in system architecture section?

It explains embedded systems, the CPU’s purpose, CPU components, the fetch–execute cycle, clock speed, and the impact of single-core versus dual-core processors and cache.

How does the networks section describe connectivity and communication concepts?

It defines networks and network types (LAN/WAN), compares client–server with peer-to-peer, discusses topologies like star and mesh, and covers performance factors, packet switching, protocols, DNS, and Wi‑Fi basics.

Sep 5, 2026

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