title: PHP session_start() function: Why I need it everytime I use anything related to PHP sessions
body: <p>For logging out a user from my website, I am redirecting the page to <code>logout.php</code> where I am using session_destroy() function. Even there also, logout functionality is not working without <code>session_start()</code> function. By adding session_start() function before <code>session_destroy()</code> function, I am able to logout the user successfully. </p>
  
  <p>Why do I need to use <code>session_start()</code> function everytime and in every page where I am doing something related to sessions? </p>