php - How to automatically eliminate the file name from the url? -

i'm using rewriteengine , rewriteconditions eliminate .php part file name.

however, visited site recently, http://poorlydrawnlines.com/comic/tragedy/. in it, mess around, tried finding actual file name, turned out index.php. however, when tried go http://poorlydrawnlines.com/comic/tragedy/index.php, site automatically shortens url http://poorlydrawnlines.com/comic/tragedy/. how behavior achieved?

also, correct in assuming page's original address ends in index.php? or site redirecting me? how recreate in own websites?

since have not provided original .htaccess code best can do.

rewritecond %{the_request} ^.*/index\.php  rewriterule ^(.*)index.php$ /$1 [r=301,l]