title: Difference between form_for and form_tag?
body: <p>I used <a href="https://github.com/curtis/honeypot-captcha">this gem</a> in my application, but I'm not sure the difference between the different implementation options for the gem:</p>
  
  <ul>
  <li>form_for</li>
  <li>form_tag with block</li>
  <li>form_tag without block</li>
  </ul>
  
  <p>Can anyone clarify?  I understand that <code>form_for</code> is used when you wish to interact with a model, but what about the other two?</p>