PHP __DIR__ returns the current working directory, its usage is common when including files as you don’t have to dynamically define the directory each time.
Simply running
echo __DIR__;
Will output the full directory up to where the script was run from.
Take this directory structure example:
root ├── dir1 ├── dir2 │ └── functions │ │ └── display.php │ │ └── database.php │ └── index.php └── index.php
dir2/index.php:
<?php include __DIR__ . "/functions/database.php"; include __DIR__ . "/functions/display.php";
as using __DIR__ here is: root/dir2
You can also use /../ to go up one level after using __DIR__
include __DIR__ . "/../somedir/file.php";
Using __DIR__ has its benefits when working in a larger project that has a deep folder structure.