What is the difference between categorical, ordinal and interval variables?
In talking about variables, sometimes you hear variables being described as categorical (or sometimesnominal), or ordinal, or interval. Below we will define these terms and explain why they are important. A categorical variable (sometimes called a nominal variable) is one that has two or more categories, but there is no intrinsic ordering to the categories.
https://stats.oarc.ucla.edu/other/mult-pkg/whatstat/what-is-the-difference-between-categorical-ordinal-and-interval-variables/
