And also see the Wikipedia, there are - Articles (about exact opening, about tactics, about the principles, etc. if u need); - Categories (e.g. the category about openings, or about the strategy, chess terminology), - Possible both categories and articles.
This is de study & discuss openings.
Perhaps one needs: https://www.365chess.com/eco.php
And also see the Wikipedia, there are
- Articles (about exact opening, about tactics, about the principles, etc. if u need);
- Categories (e.g. the category about openings, or about the strategy, chess terminology),
- Possible both categories and articles.
from here to where u want / need to.
UPD. You may look also here.
Wikibooks: the Chess Opening Theory