title: Is it totally safe to unset $_SERVER?
body: <p>As we know <code>$_SERVER</code> provides some information about the environment of the server to us and sometimes it's not reliable.</p>
  <p>We can overwrite or <code>unset()</code> the <code>$_SERVER</code> like other variables and arrays.</p>
  <p>But is it totally safe to unset this var in PHP?</p>