England · WJEC EduqasSyllabus
Computer Science syllabus, dot point by dot point
Every dot point in the England Computer Sciencesyllabus, with a focused answer for each one. Click any dot point for a worked explainer, past exam questions, and links to related dot points. Written by Claude Opus 4.8, Anthropic's latest AI.
Component 2: Computer Architecture, Data, Communication and Applications
Module overview →- How does assembly language map onto machine operations, and what do the addressing modes mean?Assembly language: the instruction set with its opcode and operand, common operations (load, store, add, jump, compare), the relationship between assembly and machine code, and immediate, direct and indirect addressing modes.13 min answer →
- How do input and output devices and the different storage technologies work, and how is the memory hierarchy organised?Input, output and storage: the role of input and output devices, the memory hierarchy from registers and cache to RAM and secondary storage, and the operating principles, advantages and uses of magnetic, optical and solid-state storage.13 min answer →
- How are computers connected into networks, what topologies and models are used, and what hardware makes a network work?Networks: LANs and WANs, network topologies (bus, star, mesh), the client-server and peer-to-peer models, and the hardware that connects a network (network interface cards, switches, routers and the role of the internet).13 min answer →
- What determines how fast a processor is, and how do RISC, CISC, multiple cores and pipelining improve performance?Processor performance: the factors affecting CPU performance (clock speed, number of cores, cache size and word length), the difference between RISC and CISC, and the use of pipelining and parallel processing.13 min answer →
- How does the processor fetch, decode and execute an instruction, and what role does each register play?The fetch-decode-execute cycle: the special-purpose registers (PC, MAR, MDR, CIR, ACC) and their use in fetching, decoding and executing an instruction, and the effect of the cycle on the registers.13 min answer →
- How is a processor organised, and what is the difference between the Von Neumann and Harvard architectures?Computer architecture: the components of the CPU (the ALU, the control unit, the registers and the system buses), the Von Neumann stored-program concept, and the difference between Von Neumann and Harvard architectures.13 min answer →
Component 1: Programming and System Development
Module overview →- How are arrays, records and other static data structures laid out in memory, and when should you choose each one?Static data structures: one- and multi-dimensional arrays, records (structs), tuples and sets, how they are stored contiguously in memory, address calculation for array elements, and choosing the appropriate structure for a task.13 min answer →
- What makes an algorithm recursive, and how does Big-O notation measure how efficiently an algorithm scales?Recursion and algorithmic complexity: the base case and recursive case, how recursion uses the call stack, and Big-O notation for the time and space complexity of algorithms (constant, logarithmic, linear, polynomial and exponential).14 min answer →
- How do linear and binary search work, how do graph traversals explore data, and how efficient is each?Searching and traversal algorithms: linear search and binary search with their conditions and efficiency, and the breadth-first and depth-first traversals of trees and graphs.14 min answer →
- How do bubble, insertion, merge and quick sort work, and which is most efficient?Sorting algorithms: bubble sort and insertion sort and their quadratic efficiency, merge sort and quick sort and their use of divide and conquer, and comparing sorting algorithms by time complexity and stability.14 min answer →
- How do stacks, queues and linked lists work, and how are they implemented and used?Dynamic data structures: stacks (LIFO) and queues (FIFO) with their push, pop, enqueue and dequeue operations and pointer management, linear and circular queues, and singly and doubly linked lists with insertion and deletion.14 min answer →
- How do trees, graphs and hash tables organise data, and what are they used for?Trees, graphs and hash tables: binary search trees and their traversals (in-order, pre-order, post-order), graphs as adjacency matrices and adjacency lists, and hashing for direct-access tables including collision handling.14 min answer →
Component 2: Computer Architecture, Data, Communication and Applications
Module overview →- How is data made smaller, kept secret, and checked for errors during storage and transmission?Compression, encryption and error checking: lossy and lossless compression (run-length encoding and dictionary methods), symmetric and asymmetric encryption, and error-detection methods (parity, checksums and check digits).14 min answer →
- How is data transmitted across networks, and what do protocols and the TCP/IP stack do?Data transmission: serial and parallel transmission, packet switching and the structure of a packet, network protocols and the layers of the TCP/IP stack, and the role of standards in communication.13 min answer →
- How is data organised in files and relational databases, and how do normalisation and SQL keep it consistent and queryable?Organisation and structure of data: files, records and fields with key fields and file access methods, relational databases with primary and foreign keys, normalisation to third normal form, and SQL for querying and manipulating data.14 min answer →
- How are real numbers stored in floating-point form, and what does normalisation achieve?Floating-point representation: storing a real number as a mantissa and an exponent in two's complement, evaluating a stored floating-point value, normalising a mantissa, and the trade-off between range and precision.14 min answer →
- How are numbers represented in binary and hexadecimal, including negatives, and how is binary arithmetic performed?Data representation of numbers: converting between binary, denary and hexadecimal, representing negative numbers with sign and magnitude and two's complement, binary addition and subtraction, and detecting overflow.14 min answer →
- How are text, images and sound represented as binary, and what determines the file size and quality?Representing text, images and sound: character sets (ASCII and Unicode), bitmap images with resolution, colour depth and the file-size calculation, and sampled sound with sample rate, bit depth and the file-size calculation.14 min answer →
Component 2: Computer Architecture, Data, Communication and Applications
Module overview →- What is the functional programming paradigm, and how do pure functions, immutability and recursion differ from imperative programming?The functional paradigm: functions as first-class values, pure functions and referential transparency, immutability and the avoidance of side effects, the use of recursion instead of iteration, and how functional differs from imperative programming.13 min answer →
- What are higher-order functions, and how do map, filter and fold process lists in functional programming?Higher-order functions and list processing: passing and returning functions, the map, filter and fold (reduce) operations, function composition, and how lists are processed by the head and tail.13 min answer →
- How does the operating system manage memory, and what are paging, segmentation and virtual memory?Memory management: how the operating system allocates and protects memory between processes, paging and segmentation, and virtual memory using secondary storage to extend the apparent size of main memory.13 min answer →
- What types of software exist, and what do utility programs do for a computer system?Software applications: the distinction between system software and application software, generic, special-purpose and bespoke applications, the role of utility programs (compression, defragmentation, backup, antivirus), and how software is licensed.13 min answer →
- What does an operating system do, and how does it manage the processor, processes and interrupts?The operating system: its role as the interface between the user, applications and hardware, process management and CPU scheduling, the handling of interrupts, and the management of input/output and the file system.13 min answer →
Component 1: Programming and System Development
Module overview →- How are logic gates, truth tables and Boolean algebra used to design and simplify digital logic?Logical operations: the logic gates (AND, OR, NOT, NAND, NOR, XOR) and their truth tables, building and reading truth tables for expressions, the laws of Boolean algebra and De Morgan's laws, and simplifying expressions with Karnaugh maps.14 min answer →
- What are the primitive data types, and how do the three programming constructs build any algorithm?Programming principles: primitive and composite data types, variables and constants, scope and lifetime, and the three programming constructs of sequence, selection and iteration used to build structured programs.13 min answer →
- What tools and structures help build a well-organised program, and how is code kept readable and maintainable?Program construction: the features of an integrated development environment (IDE), modular and structured program design, the use of libraries, and writing maintainable code with sensible naming, comments and indentation.13 min answer →
- How do procedures and the object-oriented features of classes, inheritance and polymorphism structure larger programs?Procedural and object-oriented programming: subroutines (procedures and functions) with parameters and return values, and the object-oriented concepts of classes and objects, encapsulation, inheritance and polymorphism.14 min answer →
- How are programs tested for correctness, what kinds of error occur, and how are they tracked down?Testing and correctness: the types of program error (syntax, runtime and logic), test strategies and test data (normal, boundary and erroneous), trace tables and dry runs, and validation and verification of input data.13 min answer →
- How is source code turned into something the processor can run, and what does a compiler do at each stage?Program construction and translators: compilers, interpreters and assemblers and their differences, the distinction between source, object and executable code, and the stages of compilation (lexical analysis, syntax analysis, semantic analysis, code generation and optimisation).13 min answer →
Component 1: Programming and System Development
Module overview →- What are the economic, moral, legal, ethical and cultural impacts of computer science, and which laws govern computer use?Economic, moral, legal, ethical and cultural issues: the impact of computer science on individuals and society, the relevant UK legislation (Data Protection, Computer Misuse, Copyright and Freedom of Information), and ethical concerns such as privacy, surveillance and the digital divide.13 min answer →
- What software tools support the engineering of a system, and why is version control essential to teamwork?Software engineering tools: the tools that support analysis, design, programming and testing, the role of an IDE in the development process, and version (source) control for managing changes and team collaboration.13 min answer →
- How is a system designed once its requirements are known, and what design artefacts capture the structure of its data and processing?System design: designing the inputs, outputs, processing and data structures, the use of flowcharts and pseudocode, the data dictionary, file and interface design, and specifying the hardware and software the proposed system needs.13 min answer →
- How are the requirements for a new system gathered, and how does a feasibility study decide whether to proceed?Systems analysis: identifying stakeholders, gathering requirements (interviews, questionnaires, observation, document analysis), analysing the current system, the feasibility study and its factors, and writing a requirements specification.13 min answer →
- What are the stages of the software development lifecycle, and how do the waterfall and agile approaches differ?The software development lifecycle: the stages from analysis through design, implementation, testing, installation, evaluation and maintenance, and a comparison of the waterfall and iterative or agile development methodologies.13 min answer →