title: Don't understand rewrite rule involving query string parameter
body: <p>My menu links to internal sites via</p>
  
  <pre><code>&lt;a href="&lt;?php $PHP_SELF ?&gt;?site=company"&gt;
  </code></pre>
  
  <p><code>index.php</code> includes the content in this way:</p>
  
  <pre><code>if ($_GET['site']=="company") {
      include'sites/company.php';
  }
  </code></pre>
  
  <p>So far so good. Now I searched for hours and tried a lot of stuff to rewrite the address from <code>/index.php?site=company</code> to <code>/company</code>. Nothing takes effect. One of the attempts:</p>
  
  <pre><code>RewriteEngine On
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteRule ^([\w]+)/?([\w]+)? /index.php?site=$1
  </code></pre>
  
  <p>Can anybody help, please? I´m new to <code>.htaccess</code>.</p>