title: preprocess Vs. process functions in drupal template
body: <p>What is the difference between</p>
  
  <pre><code>function mythemes_preprocess_html(&amp;$variables) { ... }
  </code></pre>
  
  <p>and</p>
  
  <pre><code>function mythemes_process_html(&amp;$variables) { ... }
  </code></pre>
  
  <p>in drupal 7 template.php.</p>
  
  <p>when must use preprocess functions and when must use process functions.</p>
  
  <p>thanks.</p>