I am currently learning the regular expressions and applications of regex in `.htaccess` file.
And in one of the videos I have seen this kind of code:

```
RewriteRule ^(.*)$ ./index.php/$1 [L]

```

So I wondered what the hell `./` is doing before `index.php`?
I tried to type `./` in the URL and it worked:

```
http://localhost/CodeIgniter3Test/./index.php/welcome

```

was redirected automatically to

```
http://localhost/CodeIgniter3Test/index.php/welcome

```

So my question is where this redirection engine is executed (file where this rule is written httpd or elsewhere) and for what reason could possibly `./` be added to the Pattern *Substitution* in `RewriteRule`?