Missing documentation/example of "categories" taxonomy

[Jens Rantil]

https://github.com/luizdepra/hugo-coder/blob/main/archetypes/posts.md contains three types of taxonomies. One of them is "categories". How do I use "categories"? Could it be added to the demo site? Document in README? How does category differ from a tag?

Background is that I am writing my first blog post series right now. But given that I don't know how I should use series (IIRC, it gave me an error). I currently link to a category to list the series, but I assume I should somehow use series.

[Luiz F. A. de Prá]

Same thing as series. hahahah