Found new "backup" folder in my site folder today

Hi, I’ve been using EE for a while, but today I noticed a new folder called “backup” in my /var/www/domain.com/ folder. Inside the folder was a folder named yesterday’s date (“24May2018065932”) with three files:

domain.com (looks like the nginx config file) domain_com.sql wp-config.php

This was in all 7 of my sites on the server. How did they get there?

Thanks!

The “backup” directory (sorry, but I hate the “new school” term, folder) is created when you issue an ee site update command.

Oh, that makes perfect sense. Thanks a lot for the answer! Agreed on the use of the term “directory”!