Question: What is a backlink about zetteldeft HOT 1 OPEN

I'll admit the term is confusing, and perhaps I should have thought of a different name.

A backlink is not special in any technical sense -- it's a plain Zetteldeft link, just like any other.
I call a backlink as a link that refers "back" to a parent note, or any overarching note that can be seen as broader parent note. So it is used to indicate hierarchy, but it's not restrictive (as in: notes can have multiple backlinks).

Backlinks are not automatically created or anytying. They are simply a way to add structure to your web of notes.

I hope this clarifies things. Also, I've slightly modified the relevant note in zd-tutorial, so you might want to check it out: https://github.com/EFLS/zd-tutorial/blob/master/2020-09-22-0855%20Backlinks.org

EDIT: I've also replied to your question on the Zettelkasten forum, here https://forum.zettelkasten.de/discussion/comment/13048/#Comment_13048

from zetteldeft.