FIDE has published a system that classifies all openings into 500 ECO codes: A00 to E99
https://nl.wikipedia.org/wiki/ECO-code#:~:text=De%20ECO%2Dcode%20is%20een,%2C%20A%20t%2Fm%20E.
HOW ARE THE OPENINGS CLASSIFIED?

FIDE has published a system that classifies all openings into 500 ECO codes: A00 to E99
https://nl.wikipedia.org/wiki/ECO-code#:~:text=De%20ECO%2Dcode%20is%20een,%2C%20A%20t%2Fm%20E.
thanks
I HAVE BEEN COLLECTING OPENINGS TO PUT INTO PRACTICE, UNTIL I FOUND OPEN, CLOSED AND SEMI-OPEN OPENINGS, I WANT TO KNOW IF THERE ARE MORE AND WHAT THE CATEGORIZATION OF OPENINGS ARE CALLED.