2. By the end of today you should know
•What is data
•How does it arise
•What forms data can take
•Why we code data
•Why we encode data
•Why data is processed
•What is information
•What affects the quality of information
4. How does data arise?
Data can arise in many ways:
•You buy something whilst shopping. The transaction generates
data that might include date, time, store, till, staff, product etc.
•You conduct an experiment and record data such as
time, pH, temperature etc.
•You are undertaking research and carry out a questionnaire or a
survey.
•A sensor collects readings from an automatic weather station
5. Direct v Indirect data
To confuse matters data can be collected directly or indirectly.
Direct data is where data is collected for and used for a given purpose.
Indirect data is where data is collected for one purpose and then used for
something completely different
A credit card company collects data about your spending in order to bill you each
month.
A secondary use of this data is to build up a “profile” of your spending habits. This
data can then be used to send you direct marketing about goods and services
that may appeal to you.
Direct Use Customer
of Data Billing
Credit Card Transaction
Indirect Use Direct
of Data Marketing
6. What types of data are there?
Data occurs in many types.
•text e.g. a, b, c, d, e ...
•numeric e.g. 0, 1, 2, 3, 4, 5...
•alphanumeric (text and numbers)
•a still image e.g. A static image taken by a digital camera or scanned in
•a moving image e.g. motion captured by a camera or phone
•sound e.g. The recording of an instrument or voice
NOTE – this is the type of data NOT the form in which it is stored
7. Why do we code data?
Data is coded before it gets anywhere near a computer system.
This is carried out for a number of reasons
