When I include files in wordpress I noticed that include works fine without get_template_directory(). Include even works fine without parenteses.
include( get_template_directory() . '/includes/front/enqueue.php' );
works fine as well as
include '/includes/front/enqueue.php';
Could anyone please explain, should I use get_template_directory() when inlcude files in wordpress?
And is it "ok" to not use parentheses after include?