I have small problem.
when i include file without ob_start, head’s codes comes in to body. So when i include without ob_start it look’s like;

and when i use ob_start it look’s like;

and my codes with ob_start
ob_start();
include("mysql.php");
ob_end_clean();
I hope it’s explained, I dont want ob_start but if i’m not use website look’s like first image. and sorry for bad english..
Your question is incomplete.Still I hope following answer helps you.
ob_start — Turn on output buffering
It is used If you really need to
echo/printsomething above yourheader/session_startcode than you have to use it.And to avoid its use you have to confirm that there is nothing (i.e text or even a
space) above your header or session_start code or it will thrown you the warning asheader already sent.