title: What HTTP header RESPONSES should I be explicitly setting when I output a webpage?
body: <p>So I just now learned of the X-Robots-Tag which can be set as part of a server response header.  Now that I have learned about this particular field, I am wondering if there are any other specific fields I should be setting when I output a webpage via PHP?  <a href="http://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Responses" rel="nofollow">I did see this list of responses</a>, but what should I be manually setting?  What do you like to set manually?</p>
  
  <p>Restated, in addition to...</p>
  
  <pre><code>header('X-Robots-Tag: noindex, nofollow, noarchive, nosnippet', true);
  </code></pre>
  
  <p>...what else should I be setting?</p>
  
  <p>Thanks in advance!</p>