AQA GCSE COMPUTER SCIENCE
Specification Checklist
AQA Specification Code 8520
AQA GCSE Computer Science (8520)
Specification Checklist (page 1)
Data Representation
Convert numbers up to 255 between: decimal (base 10), binary (base 2), hexadecimal (base 16)
Know units of information: bit (b), byte (B), kB, MB, GB, TB
Add together up to three binary bytes.
Apply a binary shift to a binary byte.
Describe the ASCII and Unicode character sets.
Describe how a bitmap represents an image using pixels and colour depth.
Calculate bitmap image file sizes (width x height x colour_depth)
Describe the digital representation of sound in terms of sampling rate and sample resolution.
Understand why data may be compressed.
Be able to interpret/create Huffman trees (for data compression).
Be able to represent data with Run Length Encoding (RLE).
Computer Systems
Define the terms hardware and software.
Construct truth tables for the following logic gates: NOT, AND, OR
Construct and interpret truth tables for simple logic circuits (up to 3 inputs).
Construct and interpret circuit diagrams for simple logic circuits.
Give examples of system software and application software.
Understand the functions of operating systems and utility applications.
Explain the Von Neumann CPU architecture (main memory, ALU, control unit, clock, bus).
Explain how CPU performance is affected by: clock speed, cores, cache size/type.
Understand the Fetch-Decode-Execute cycle.
Understand the differences between ROM, RAM, main memory and secondary storage.
Explain the operation of solid-state, optical and magnetic secondary storage.
Explain the term “cloud storage”.
Explain how an embedded computer system differs from a non-embedded system.
AQA GCSE Computer Science (8520)
Specification Checklist (page 2)
Networks
Describe the main types of computer network: PAN, LAN, WAN
Discuss benefits and risks of wireless vs wired networks.
Explain star and bus network topologies.
Explain network protocols: Ethernet, Wi-Fi, TCP, UDP, IP, HTTP, HTTPS, FTP, SMTP, IMAP
Cyber Security
Define the term cyber security.
Explain white-box and black-box penetration testing.
Explain the following forms of social engineering: blagging, phishing, pharming, shoulder-surfing
Describe the following forms of malicious code: virus, Trojan, spyware, adware
Explain the following security measures: biometrics, passwords, CAPTCHA, email confirmation,
software updates
Algorithms
Explain the terms algorithm, decomposition and abstraction
Represent algorithms using pseudo-code and flowcharts.
Explain simple algorithms in terms of their inputs, processing and outputs.
Compare the efficiency of different algorithms.
Compare and contrast linear search and binary search algorithms.
Explain and compare merge sort and bubble sort algorithms.
Ethical, Legal and Environmental Impacts of Digital Technology
Topics include: privacy, cyber security, mobile technologies, wireless networking, cloud storage,
theft of computer code, copyright of algorithms, cracking, hacking, wearable technologies, implants
AQA GCSE Computer Science (8520)
Specification Checklist (page 3)
Programming
Understand the data types: integer, real, Boolean, character, string
Be able to declare and assign a value to a variable or constant.
Use definite and indefinite iteration.
Use nested selection and nested iteration.
Use arithmetic operators: add, subtract, multiply, real number division, integer / remainder division
Use relational operators: ( == ) ( != ) ( < ) ( > ) ( <= ) ( >= )
Use Boolean operators: NOT, AND, OR
Use arrays/lists (one and two-dimension).
Be able to obtain user input from the keyboard.
Be able to read from (and write to) a text file.
Be able to use random number generation.
Understand and explain the concept of subroutines/functions.
Use parameters to pass data (to subroutines/functions) within programs.
Use subroutines/functions that return values.
Explain why it is good practice to use local (rather than global) variables.
Be able to write simple data validation routines.
Be able to write simple (non-encrypted) authentication routines.
Select suitable test data that covers typical, boundary and erroneous data.
Explain the differences between low-level and high-level programming languages.
Explain the differences between machine code and assembly language.
Explain the differences between program translators: interpreter, compiler, assembler
Software Development
Design: Be aware that before constructing a solution, the solution should be designed.
Implementation: Writing, debugging and testing programs.
Testing: Be aware that a solution must be tested for errors using test data (typical, boundary, erroneous).
Evaluation/Refining: Be aware that code created during implementation will often require refining as a
result of testing.