That Blue Square Thing

AQA Computer Science GCSE

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

Data Representation – Binary Bits and Bytes

You need to know about how binary digits form Bytes, kiloBytes, MegaBytes and so on. And nibbles.

PDF iconBinary Numbers – bits and bytes – lots of important terminology here

Converting between Units of Information

By Units of Information, I mean kiloBytes, MegaBytes, GigaBytes, TerraBytes and so on.

You need to be able to convert between these – so change 8 GB into kiloBytes or 48,000 bits in MegaBytes. The maths of this isn't too hard, but it's tricky to get your head around exactly how to do this.

PDF iconConverting between Units of Information – how to convert

Questions to try:

PDF iconUnits of Information questions – in exam style

Try using the table first to work out how to convert from larger to smaller units. Then you can use the worked examples to figure out how to convert both ways. Then there are some questions to try.

PDF iconUnits of Information table – works on converting from larger to small units (e.g. GB to kB)

PDF iconUnits of Information worked examples – examples showing (I hope) how to convert from larger to smaller and smaller to larger units

Revision Summary

The key slides:

PDF iconUnits of Information Summary

PDF iconHow to Convert – summary