Computer Science - OCR

Get ready for your OCR computer science GCSE exams with free interactive tests and feedback to improve your knowledge of binary, programming techniques and more.

Free interactive OCR computer science GCSE questions based on past papers. Boost your knowledge of algorithms, computer systems, data structures and more.

Von Neumann architecture provides the basis for the majority of the computers we use today. The fetch-decode-execute cycle describes how a processor functions.

Primary memory is a key component of a computer system. Its function is to hold data and programs that are currently in use.

All data is represented as binary digits, whether it is numbers, text, images or sound. Calculations are also done in binary.

Networks can be arranged in different topologies. Encryption is used to ensure that messages can be sent securely over a network.

Networking computers brings many benefits to users. Without networking, many computing applications would not be possible.

Networks operate on the principles of communication and sharing. Unfortunately, these principles mean that network traffic and data can be more easily subject to access by people who have no authority to do so.

A computer is controlled by systems software. Operating systems provide this control, while utilities help to maintain the system.

The use of computers has brought about ethical, legal, cultural and environmental impacts. These issues increasingly affect people's daily lives.

Computers can be used to help solve problems. However, before a problem can be tackled, it must first be understood. Computational thinking helps us to solve problems.

Algorithms are step-by-step plans for solving problems. Algorithms can be designed using pseudocode and flow diagrams.

Sorting and searching are two of the most frequently needed algorithms in program design. Standard algorithms have evolved to take account of this need.

Programs are designed using common building blocks, known as programming constructs. These programming constructs form the basis for all programs.

Proficient programming requires knowledge of many techniques. These techniques allow for powerful, complex programs.

Programs must run correctly or they are of little value. Careful planning and testing of a program are essential, as is writing maintainable code.

At the simplest level, computers are little more than a collection of transistors and circuits. They connect together to form logic gates, which in turn are used to form logic circuits.

Translators are needed to translate programs written in high level languages into the machine code that a computer understands. Tools exist to help programmers develop error-free code.

Every programming problem needs decomposing so that it can be properly understood. From this, an algorithm can be designed and tested.

Essay-style questions are worth a lot of marks. They test not only understanding, but whether or not your knowledge and understanding can be put into a coherent argument.