That Blue Square Thing

Syllabus content:
PDF iconUnit 3 content – PDF doc to download
Note: this syllabus content is a slightly amended version of the one published freely on the web by AQA. I have made very minor adjustments to remove some content less suitable for students to use and it is presented here simply to allow the children I teach to download a usable copy of the syllabus content. It is copyright AQA and reproduced here simply to make access easier for students. No attempt to claim copyright is being made, although I could have copied the text into my own interpretation...

AQA Computer Science GCSE

This page is up to date for the AQA 8525 syllabus for exams from 2022.

Data Representation

This part of the course is all about understanding how computers use binary numbers to store information and instructions. This includes text, images and sound as well as instructions in programs and more complex data such as video files.

There are five main parts of the syallabus here:

  1. Binary numbers
  2. Characters, words and text
  3. Images – pictures and photographs
  4. Sound files
  5. Data compression

None of this is too hard in itself, although some of the binary and hexadecimal is a bit tricky. But it's stuff that you have to actually learn and practice doing to be confident with in an exam.

How computers work

Before you start, it's useful to know how computers work and why they have to use binary numbers for everything.

PDF iconWhat do computers do? – slides from class

PDF iconTask

PDF iconPaper version of task

So, how do computers actually deal with numbers?

PDF iconSwitches – how computers deal with numbers

PDF iconSwitches table