Data in separate categories. E.g, grouping people according to their favourite football team.
What is ordinal data?
Data ordered in some way e.g, list of football teams in order of liking. 'Difference' between each item is not same e.g, person may like first item lot more than second, but might only be small difference between items ranked second & third.
What is interval data?
Data measured using units of equal intervals. E.g, time in seconds & weight in grams.
What is ratio data?
There's a true 0 point (interval data). E.g, Temperature in Kelvin can't go below 0.
