This visually appealing knowledge organiser helps pupils revise binary, denary, hexadecimal, binary addition, binary shift, ASCII, Unicode, bitmaps, sound and data compression for the GCSE in Computer Science. Written originally for OCR Computer Science (J276), it is also suitable for helping pupils revise for other exam boards.


One PDF document contains a 2-page PDF knowledge organiser and another PDF document which includes tips of revision techniques allowing pupils to pick a technique they prefer. Once they have revised the topic, they can attempt the 4 mark exam practise question on the second sheet and mark it themselves using the mark scheme included.


This resource makes an ideal homework task, can be used as part of a lesson or given to pupils to help them with their exam revision.



  • Data units
  • Converting denary whole number to binary
  • Add binary numbers
  • Use binary shifts
  • Convert binary into hexadecimal numbers
  • The use of check digits
  • Representing characters
  • Character sets
  • Representing images in pixels
  • Metadata
  • Colour depth
  • Resolution
  • Calculating the size of an image
  • Sound sampling
  • Sample size
  • Bit rate
  • Lossy and lossless compression

Data Representation Knowledge Organiser

  • Digital resources purchased from Nichola Wilkin Ltd. are to be used in the original individual school which purchases the resources only.


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