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2.3

Data Representation

Binary, hexadecimal, images, sound

Binary: Base 2 (0,1), Hexadecimal: Base 16 (0-9, A-F)

8 bits = 1 byte, can represent 0-255

Two's complement for negative numbers

Character encoding: ASCII (7-bit), Unicode (multi-byte)

Images: Resolution x colour depth = file size

Sound: Sample rate x bit depth x duration = file size

Exam Tips

  • Always define key terms before explaining concepts
  • Use specific examples where possible to demonstrate understanding
  • Check mark allocation - one point per mark is a good guide