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.
Algorithms and computational thinking
Module overview →- What are abstraction, decomposition and algorithmic thinking, and how do they help you solve a problem with a computer?Computational thinking: abstraction, decomposition and algorithmic thinking, and how these techniques are used to break down and solve a problem.9 min answer →
- How do you design an algorithm using pseudocode and flowcharts, and how do you trace one to check it works?Designing, expressing and tracing algorithms using pseudocode and flowcharts, and using a trace table to follow an algorithm step by step.11 min answer →
- What do the AND, OR and NOT logic gates do, and how do you build and read a truth table?The logic operators AND, OR and NOT, their logic gates and truth tables, and combining them in simple logic circuits and Boolean expressions of up to three inputs.10 min answer →
- How do linear search and binary search work, and when is each one the right choice?The linear search and binary search algorithms, how each works, the requirement that binary search needs sorted data, and how their efficiency compares.10 min answer →
- How do the bubble sort and merge sort algorithms put a list in order, and how do they compare?The bubble sort and merge sort algorithms, how each puts a list into order, and how their efficiency on large lists compares.10 min answer →
Data representation and storage
Module overview →- How do you add two binary numbers, and what does shifting the bits left or right do?Binary addition of two 8-bit numbers including carrying and overflow, and binary shifts (left and right) and their effect of multiplying or dividing by powers of two.11 min answer →
- How is text stored in binary, and why was Unicode needed when ASCII already existed?How text is represented using character sets, the ASCII character set, the need for and nature of Unicode, and how a character maps to a binary code.9 min answer →
- Why is data compressed, and when should you use lossy rather than lossless compression?The purpose of compression, the difference between lossy and lossless compression, and how to choose the appropriate type for a given scenario.9 min answer →
- How do you convert a number between binary, denary and hexadecimal?Number systems: binary, denary and hexadecimal, and how to convert between all three, including why hexadecimal is used as a shorthand for binary.12 min answer →
- How does a computer store a negative whole number in binary?Signed and unsigned binary, and the use of two's complement to represent negative integers, including converting between two's complement and denary for 8-bit numbers.10 min answer →
- What are the units of data, and how do you calculate the size of an image or sound file?The units of data (bit, nibble, byte, kilobyte, megabyte, gigabyte, terabyte), how images are stored as pixels (resolution and colour depth), how sound is sampled (sample rate and bit depth), and calculating file sizes.12 min answer →
Hardware and architecture
Module overview →- What is cloud storage, and what makes an embedded system different from a general-purpose computer?Cloud storage and its advantages and disadvantages, and the characteristics and uses of embedded systems compared with general-purpose computers.9 min answer →
- How does the processor fetch and carry out a single program instruction?The purpose of the CPU, the fetch-decode-execute cycle, the von Neumann architecture, and the function of the common CPU components and registers (ALU, control unit, PC, MAR, MDR, accumulator).11 min answer →
- Why is one processor faster than another, and why does adding cores not always double the speed?The factors that affect CPU performance: clock speed, the number of cores, and the size and use of cache memory, and how each one changes how quickly programs run.10 min answer →
- What are input and output devices, and how do you choose suitable ones for a given system?The purpose of input and output devices, common examples (including sensors and actuators), and how to choose suitable devices for a given system or user.9 min answer →
- What is the difference between RAM, ROM and secondary storage, and how do you choose a storage device?Primary storage (RAM, ROM and virtual memory), the need for and types of secondary storage (magnetic, optical and solid state), and the factors used to choose a storage device.11 min answer →
Impacts and legislation
Module overview →- What environmental harm does digital technology cause, and how can it be reduced?The environmental impacts of digital technology, including energy consumption, the resources used to make devices, electronic waste (e-waste), and reuse and recycling.9 min answer →
- What ethical, cultural and social issues does digital technology raise for individuals and society?The ethical, cultural and social impacts of digital technology, including the digital divide, the effect on employment and working practices, and issues such as misinformation and online behaviour.9 min answer →
- What does each of the main computing laws cover, and what does it make illegal?The relevant legislation: the Data Protection Act, the Computer Misuse Act, and the Copyright, Designs and Patents Act, including what each covers and the offences under each.10 min answer →
- How does the collection and tracking of data affect personal privacy, and what is the trade-off involved?Privacy and the impact of data collection, tracking and surveillance, including cookies and location data, and the balance between privacy, security and convenience.9 min answer →
Networks and security
Module overview →- What are the main cybersecurity threats to a computer system or network, and how does each one work?The common cybersecurity threats: malware, phishing, social engineering, brute-force attacks, denial-of-service attacks and SQL injection, and how each one works.11 min answer →
- What is the difference between a LAN and a WAN, and how do the bus, star and mesh topologies compare?LANs and WANs and the benefits and drawbacks of networking, and the bus, star and mesh network topologies with their advantages and disadvantages.10 min answer →
- How can a system be protected against attack, and how should data be backed up and managed?The methods used to protect a system (firewalls, encryption, passwords and biometrics), and data management including the need for and types of backup.10 min answer →
- What is the difference between the internet and the web, and what does each common protocol do?The internet, the World Wide Web and DNS, and the purpose of the common protocols: TCP/IP, HTTP, HTTPS, FTP, SMTP, POP and IMAP.10 min answer →
- Why is network communication organised into layers, and what are the advantages of doing so?The concept of a layered model for network protocols, the role of layers, and the advantages of using a layered approach.9 min answer →
- How do wired and wireless connections compare, and what does each piece of network hardware do?Wired and wireless connections and their advantages and disadvantages, and the purpose of common network hardware: the network interface card (NIC), switch, router and wireless access point.9 min answer →
Programming
Module overview →- What are the main data types, and how do the arithmetic, relational and logical operators work?Variables and constants, the common data types (integer, real, Boolean, character, string), and the arithmetic, relational and logical operators used in programs.10 min answer →
- What is an array, and how do you store and process many values with one?Arrays as a data structure: declaring and using one-dimensional arrays, accessing elements by index, and iterating through an array with a loop, with awareness of two-dimensional arrays.10 min answer →
- What is the difference between high-level and low-level languages, and what does each kind of translator do?High-level and low-level languages, machine code and assembly language, the three translators (compiler, interpreter and assembler), and the features of an integrated development environment (IDE).11 min answer →
- What does an operating system do, and what is utility software for?The purpose and functions of an operating system (memory management, multitasking, peripheral management, the user interface, and security and user management) and the role of common utility software.10 min answer →
- What are the three programming constructs, and how do you use selection and the two kinds of iteration?The three programming constructs: sequence, selection (if and nested if) and iteration (count-controlled and condition-controlled loops), and when to use each.11 min answer →
- How do you work with text in a program, and how do you validate input in the on-screen exam?String handling (length, indexing, substrings, concatenation, case conversion), input validation (presence, range, length, type and format checks), and how programs are written and tested in the Component 2 on-screen exam.11 min answer →
- What is a subprogram, and what is the difference between a procedure and a function?Subprograms (procedures and functions), the difference between them, parameters and arguments, local and global variables, and why subprograms make programs easier to write and maintain.10 min answer →