Data And Information
- 2. What is data? Raw facts and figures or a set of values, measurements or records of transactions NOTE: Data is the plural, datum is the singular
- 3. What is information? Data that has been processed and gives us knowledge
- 4. Sources of data Surveys Output from a MIS From a transaction From the results of an experiment From (automatic) measurement of certain qualities (eg environmental)
- 5. What forms can data take? Numbers Words Images Sound
- 6. Why code data? Less effort to type in More data can appear on the screen at one time Takes up less storage space It is easier to check that a code is accurate using validation checks
- 7. Coding v Encoding CODING Some data is coded on collection before being entered and this changes the original data into a shortened version by assigning a code ENCODING This is used by computers to convert the data into machine readable form
- 8. Encoding Text and numbers commonly encoded using ASCII (American Standard Code for Information Interchange) Images and sound encoded in various file format – some are lossy and some lossless
- 9. ASCII and Binary All characters are represented by a number in ASCII The numbers are translated into binary code which is the format required by the computer The binary code has 8 digits per character Each digit is a bit and 8 digits is a byte