Computer Science GCSE revision course in London (Easter)



Why do an Easter Revision Course at Ashbourne?

The course leader for the Easter Computing Revision Course is Ruchi Agarwal. Students will benefit from her vast and diverse experience as well as the individual attention which is a key feature of the Ashbourne Easter Revision programme.

There will be revision in the following areas:

Unit A451: Computer Systems and Programming

Fundamentals of computer systems:

  • introduction to computer systems and how they comprise hardware and software, how data is converted into the computer’s internal representation and processed and then output
  • How the data is stored for later use or to be transmitted to another computer system
  • Understanding of computer systems and the need for reliability, professional standards and ethical considerations.

Computing hardware

  • Hardware and the Central Processing Unit (CPU), its purpose, function and the common characteristics of CPUs
  • Binary logic, reasons for its use, logic diagrams and truth tables Memory
  • The difference between RAM and ROM
  • The need and purpose of RAM and ROM, the impact on the performance of the amount of RAM
  • Virtual memory, cache memory, flash memory input and output devices
  • The need for input and output devices
  • Suitable input and output devices for w wide range of controlled situations and specific needs

Secondary storage

  • The different storage technologies and their use for different applications according to their characteristics


  • The need, purpose and use of common utility programs for computer security, disk organization and system maintenance

Representation of data in computer systems

  • Data units vocabulary (e.g. byte, megabyte…)
  • Converting positive denary whole numbers into binary numbers and vice versa
  • Converting positive denary whole numbers into hexadecimal numbers
  • The use of binary code to represent characters and character set
  • The representation of an image as a series of pixels represented in binary and metadata such height, width and colour depth and its effect on image size
  • The sampling and storage of sound in a digital form
  • Instructions and how they are coded and distinguished by computers


  • The concept of database and how the use of data handling software to run a database
  • How DBMS and their principal features in allowing the separation of data from applications
  • The relationship between the components of a database

Computer communications and networking

  • Stand-alone computers into a local area network and the hardware needed
  • Client-sever, peer-to-peer, ring, bus and star networks
  • The differences between a local network and a wide area network like the internet
  • The need for security measures in networks

The Internet

  • The nature of the internet and the hardware needed
  • Addressing of resources, files and compression


  • Algorithms, written in pseudocode or flow diagrams
  • The difference between high level code and machine code and the different components of translators
  • Control flow in imperative languages by the use of sequence, selection and iteration in algorithm
  • Handling data in algorithms, using the terms variables and constants
  • Understanding the different data types: integer, real, Boolean, character and string
  • Using one-dimensional arrays
  • Syntax and logic errors while developing a program, testing data
See our full list of GCSE revision courses in London or read more about our Easter Revision Course programme.