OCR GCSE Computer Science Active Recall Guide (J277)
OCR · GCSE
OCR GCSE Computer Science Active Recall Guide
Every topic of specification J277 written as exam-style questions with the answers printed after them. 740 questions across 11 topics and 46 subtopics, covering both papers with no options left out.
- OCR
- GCSE
- Specification J277
- 740 questions
Guide overview All 11 topics Sample questions Papers and weighting Look inside Questions and answers
What the exam asks of you
OCR GCSE Computer Science is examined in two papers of 1 hour 30 minutes, each worth half the GCSE. J277/01, Computer Systems, covers the CPU, memory and storage, networks and their security, systems software, and the impacts of digital technology. J277/02, Computational Thinking, Algorithms and Programming, covers algorithms, programming fundamentals, robust programs, Boolean logic and programming languages.
There are no options. Every student studies all eleven topics, and both papers are written rather than on-screen, so the programming is examined on paper in OCR Exam Reference Language.
| Paper | Covers |
|---|---|
|
J277/01 Computer systems |
SYSTEMS ARCHITECTURE MEMORY AND STORAGE COMPUTER NETWORKS, CONNECTIONS AND PROTOCOLS NETWORK SECURITY SYSTEMS SOFTWARE ETHICAL, LEGAL, CULTURAL AND ENVIRONMENTAL IMPACTS OF DIGITAL TECHNOLOGY |
|
J277/02 Computational thinking, algorithms and programming |
ALGORITHMS PROGRAMMING FUNDAMENTALS PRODUCING ROBUST PROGRAMS BOOLEAN LOGIC PROGRAMMING LANGUAGES AND INTEGRATED DEVELOPMENT ENVIRONMENTS |
What is in the guide
All 11 topics
Every topic has its own page with its subtopics, what it covers and sample questions.
Sample questions
Taken from the guide. Answer each one closed book first, then open the answer.
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CPU components and the fetch-execute cycle
What is the role of the Control Unit?
Show the answer
The Control Unit decodes instructions and sends control signals to coordinate the other parts of the CPU. The CU also controls the flow of data between the CPU and memory. -
RAM, ROM, cache and virtual memory
What does it mean to say that RAM is volatile?
Show the answer
Volatile memory loses its contents when the power is switched off. RAM needs a constant power supply to keep its data. -
LANs, WANs and network performance
Why would a bank with branches all over the country use a WAN?
Show the answer
A WAN links every branch to the bank's central systems. Staff in any branch can then reach the same customer records and accounts. -
Malware, social engineering and brute-force attacks
What is spyware, and what is its purpose?
Show the answer
Spyware secretly monitors what a user does on their computer. A keylogger is spyware that records keystrokes to capture passwords and card numbers. -
User interfaces, memory management and multitasking
Why might an experienced technician prefer a command-line interface to a GUI?
Show the answer
Typed commands can be quicker for someone who knows them, and they can be combined into scripts to automate tasks. A command-line interface also uses far less memory and processing power. -
Ethical and cultural issues in digital technology
How can bias in artificial intelligence be an ethical problem?
Show the answer
An AI system learns from past data, and that data may reflect unfair human decisions. The system can then treat some groups unfairly, for example when screening job applications. -
Abstraction, decomposition and algorithmic thinking
What can go wrong if abstraction removes too much detail?
Show the answer
A model that ignores an important detail gives inaccurate results. A weather forecast that left out wind speed would make poor predictions. -
Variables, constants, operators and assignment
What is output by x = 4, then x = x + 3, then x = x * 2, then x = x - 5, then print(x)?
Show the answer
The code outputs 9. The value of x goes from 4 to 7, then to 14, then to 9.
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Look inside
Questions for a subtopic print together and the answers for that section print after them.
- Systems Architecture46
- Memory and Storage143
- Computer Networks, Connections and Protocols99
- Network Security51
- Systems Software45
- Ethical, Legal, Cultural and Environmental Impacts of Digital Technology64
- Algorithms81
- Programming Fundamentals99
- Producing Robust Programs48
- Boolean Logic32
- Programming Languages and Integrated Development Environments32
- What is primary storage?
- Why does a computer need primary storage as well as secondary storage?
- Which types of memory make up primary storage?
- What does RAM stand for, and what is its purpose?
- What does ROM stand for, and what is its purpose?
- What does it mean to say that RAM is volatile?
- Why must ROM be non-volatile?
- State three differences between RAM and ROM.
- A student is typing an essay when the power fails. Why is the unsaved work lost?
- Primary storage is the memory that the CPU can access directly. Primary storage holds the data and instructions currently in use.
- The CPU needs very fast access to the programs and data it is running. Secondary storage is far too slow for the CPU to work from directly.
- Primary storage is usually made up of RAM and ROM. Cache is also a form of primary storage.
- RAM stands for random access memory. RAM holds the operating system, programs and data that are currently in use.
- ROM stands for read-only memory. ROM holds the start-up instructions, such as the BIOS, that get the computer running when it is switched on.
- Volatile memory loses its contents when the power is switched off. RAM needs a constant power supply to keep its data.
- The start-up instructions must be available every time the computer is switched on. Non-volatile memory keeps its contents without power.
- RAM is volatile, but ROM is non-volatile. RAM can be read and written, while ROM can normally only be read. RAM has a much larger capacity than ROM.
- The unsaved essay was held only in RAM. RAM is volatile, so its contents disappear as soon as the power is cut.
questions
Scroll sideways to turn through the pages.
Questions students ask first
Which topics are on which paper?
J277/01 is Systems Architecture, Memory and Storage, Computer Networks, Network Security, Systems Software, and the Ethical, Legal, Cultural and Environmental Impacts of Digital Technology.
J277/02 is Algorithms, Programming Fundamentals, Producing Robust Programs, Boolean Logic, and Programming Languages and IDEs. The breakdown is here.
Which programming language do I need?
Neither paper requires a specific language. OCR uses its own Exam Reference Language on the written papers, and you can answer in that, in pseudocode or in a high level language. The guide asks what constructs do and what algorithms produce rather than the syntax of any one language.
Is the programming project examined?
No. The programming project is a practical activity your school runs, and it does not count towards the grade on J277. Both papers are written.
Are the binary and hex conversions covered?
Yes. Denary, binary and hexadecimal conversions, binary addition and shifts, overflow, character sets, images and sound, units of storage and compression, all inside Memory and Storage which is 143 questions.
OCR GCSE Computer Science Active Recall Guide
Every question paired with its answer, grouped by topic and subtopic, ready to work in three passes.