Explanations

From https://diataxis.fr/reference/:

Reference material contains propositional or theoretical knowledge that a user looks to in their work.

The only purpose of a reference guide is to describe, as succinctly as possible, and in an orderly way. Whereas the content of tutorials and how-to guides are led by needs of the user, reference material is led by the product it describes.

Reference - information oriented, theoretical knowledge, that serves our work In the case of software, reference guides describe the software itself - APIs, classes, functions and so on - and how to use them.

Your users need reference material because they need truth and certainty - firm platforms on which to stand while they work. Good technical reference is essential to provide users with the confidence to do their work.