Topic 2: Data and Information

• Aspects of data

DATA: raw facts and figures or a set of values, measurements or records of transactions

• Ways in which data can arise:
  • From a survey
  • From the output of a management information system
  • From a transaction
  • From the results of an experiment
  • From automatic measurement of environmental qualities

Coding data:

• Coded data takes less effort to type in
• More data can appear on the screen
• Takes up less storage space (less important as storage media is cheap)
• Easier to check that a code is accurate using validation checks
• Encoding data:
  • Pricess of putting information/data into a specified format that allows effective transmission or storage by an ICT system
  • Only able to process data in binary code, so any data has to be converted to this format before processing
  • Opposite is decoding when the coded information is changed back into its original form
• Examples of encoding:
  • ASCII (America Standard Code for Information Interchange) encoding - here characters on the keyboard are changed into a series of binary digits
  • Reasons for encoding:
    • To compress data - occupies less space on a storage device and makes it faster to send to another computer over a network
    • To enable a file produced in one software package to be read by someone who does not have that software package available on their computer
• Encoding image files:
  • Image is represented in a certain way when it is stored
  • Different ways in which image can be encoded depends on how the image is taken
• Data representation:
  • When a character is typed from the keyboard it is converted to a binary code which consists of a series of 1's and 0's. This is then processed by the computer
  • Binary coded characters are transmitted along a wire until teh character is recieved at the other end where it is decoded and converted back to teh character again

Types of encoding for sound files

Sound is quite complex and requires a lot of storage space, compression is used during encoding. Formats for sound files:

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    • WAV - used with Windows for storing sounds…