units of data

• bit 


  symbol: b

  binary value: 0 or 1
• nibble


  binary value - 4 bits

  approximation - 1/2 bytes
• byte


  symbol: B

  binary value: 8 bits

  approximation: 1 byte
• Kilobyte


  symbol: KB

  binary value: 1024 bytes

  decimal value: $10^3$

  approximation: 1000 bytes

  written: thousand bytes
• Megabyte


  symbol: MB

  binary value: $1024^2$bytes

  decimal value: $10^6$

  approximation: 1,000,000

  written: million bytes
• electronic components: are easy to manufacture, therefore cheaper and more reliable
• examples of using two states to store data

  RAM

  hard disk

  optical disk

  flash memory
• Gigabyte


  symbol: GB

  binary value: $1024^3$ bytes

  decimal value: $10^9$

  approximation 1000000000 bytes

  written: billion bytes
• terabyte


  symbol: TB

  binary value:$1024^4$ bytes

  decimal value: $10^12$ bytes

  approximation: 1,000,000,000,000 bytes

  written: trillion bytes
• Petabyte


  symbol: PT

  binary value: $1024^5$ bytes

  decimal value: $10^15$

  approximation: 1000000000000000

  written: quadrillion bytes
• bit -> byte (/8)

  byte -> bit (x8)

  kilobyte -> megabyte (/100)
• calculate text files

  bits per character x number of characters
• calculating image files

  colour depth x image width
• calculating sound files

  sample rate x duration in seconds x bit depth