title: Where are these extra HTTP headers coming from?
body: <p>When I simply echo something out of php file, I do not send any headers intentionally, however - there are some default headers present anyway when I look at firebug response:</p>
  
  <p>response headers:</p>
  
  <blockquote>
    <p>HTTP/1.1 200 OK<br>
    Server: nginx<br>
    Date: Thu, 23 Jun 2011 19:33:51 GMT<br>
    Content-Type: text/html<br>
    Transfer-Encoding: chunked<br>
    Connection: keep-alive<br>
    Vary: Accept-Encoding<br>
    X-Powered-By: PHP/5.3.6-6~dotdeb.1<br>
    Expires: Thu, 19 Nov 1981 08:52:00 GMT<br>
    Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0<br>
    Pragma: no-cache<br>
    Content-Encoding: gzip</p>
  </blockquote>
  
  <p>I'm curious - are these default response headers set by the server(nginx) or by PHP?</p>