title: What session functions have to be called before html tag
body: <p>I've heard that <code>session_start()</code> needs to be called before the <code>!DOCTYPE</code>, but I am confused about other session functions. From the manual:</p>
  
  <pre><code>"To use a named session, call session_name() before calling session_start()."
  </code></pre>
  
  <p>So, I obviously have to have the <code>session_name()</code> function before the <code>&lt;!DOCTYPE html&gt;</code>, but what other functions do I need before the html begins? I'm pretty sure that <code>$_SESSION['']</code> is okay inside the html, but I would just like to clarify.</p>