Why Using @ When Using mkdir() ?

why? and if I don't use @, What Happens?

example : @mkdir ($this->getDataFolder());

 

The @ ignores any error message made by the mkdir() function or any other function https://www.php.net/manual/en/language.operators.errorcontrol.php
mkdir() will throw an error if the directory exist or if the permission was denied
if you remove it, (you guessed it) any error made by the function won't be ignored
btw why tf do people still do @mkdir($this->getDataFolder());

 

The @ supresses any warning and errors that might be generated. You can read more about it right here:
https://www.php.net/manual/en/language.operators.errorcontrol.php

from the PHP website ^^

(GG @mmm545 for being earlier xD)