Data can be of different types:
Numeral (quantitative)
- Discrete (integer; for example counts or date grouped by year)
- Continuous (real number; for example height as measured. However, if rounded to the nearest cm the data would become discrete)
Categorical (qualitative)
- Nominal (different groups; for example dome osteotomy and wedge osteotomy)
- Ordinal (ordered groups; for example bed ridden, walking with frame, walking with sticks, walking unaided)
- Binary (yes / no ; true / false ; dead / alive)
The appropriate type of statistical analysis depends on the type of data.
What type of plot is appropriate depends mainly on the type of data to be presented.