Classifier / categories
gender
nationality
bins and groups
no ordering
mode
classifier / categories
experience of programmer
can not calculate mean
nominal which can be ordered
grades
same distance between the categories
age of the project
you can force it but it makes naturally no sense
number
10.5
have a count
lines of code
amount of classes
People
Project Manager A
Project Manger B
Infrastructure
Project Management Tool
Analyse Tool
lines of code
you see it directly
without the behaviour
behaviour of the entity in the environment
usability