ICT Topic 1 - Data

ICT Topic 1 - Data

1. Evaluating Data

   • GIGO: Abbreviation for garbage in garbage out. It means if you out rubbish into the computer then you get rubbish out.
   • DATA: Raw facts and figures, e.g. readings from sensors and survey facts, etc.
   • Processing: Performing calculations or arranging the data into a meaningful order
   • Transaction: A piece of business, e.g. an order, purchase, return, delivery, transfer of money etc.
   • Information: Data that has been processed by the computer.
   • Knowledge: Derived from information by applying rules to it

2. Encoding Data

   • Encoding: Putting data into code.
   • Advantages of encoding
     • Takes up less storage space
     • Easily transferable
     • Easier to back up
   • Disadvantages of encodng
     • Easily stolen
     • Training needed
     • Security problem

3. Data Validation

   • Transcription error: Error made when typing in data using a document as the source of the data.
   • Transposition error: Error made when characters are swapped around so they are in the wrong order.
   • Check digit: A decimal number (or alphanumeric character) added to a number for the purpose of detecting the sorts of errors we make on data entry.
   • Range check: Data validation technique which checks that the data input to a computer is within a certain range.
   • Presence check: Is used to check that data is entered into the correct fields. For example entering your username and password on the computer.
   • Validation checks: Checks a developer of a solution sets/creates, using the software, to restrict the data that a user can enter, to reduce errors.

4. Data Verification

   • Batch total: A meaningful total that is used to check that the computer has input all the data.
   • Hash total: Meaningless total of numbers, such as order numbers, used to check that all the data has been entered.
   • Parity check: Check to make sure that the data sent is the same as that received when data is transmitted from one computer to another.
   • Verification: Checking that the data being entered into the ICT system perfectly matches the source of the data.